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BREAKING BOUNDARIES:
A STUDY OF HUMAN-MOBILE INTERACTION
A DISSERTATION
SUBMITTED TO THE DEPARTMENT OF COMMUNICATION
AND THE COMMITTEE ON GRADUATE STUDIES
OF STANFORD UNIVERSITY
IN PARTIAL FUFLILLMENT OF THE REQUIREMENTS
FOR THE DEGREE OF
DOCTOR OF PHILOSOPHY
Katherine Janice Murray
May 26, 2011
http://creativecommons.org/licenses/by-nc/3.0/us/
This dissertation is online at: http://purl.stanford.edu/qj975qc0870
© 2011 by Katherine Janice Murray. All Rights Reserved.
Re-distributed by Stanford University under license with the author.
This work is licensed under a Creative Commons Attribution-Noncommercial 3.0 United States License.
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I certify that I have read this dissertation and that, in my opinion, it is fully adequatein scope and quality as a dissertation for the degree of Doctor of Philosophy.
Clifford Nass, Primary Adviser
I certify that I have read this dissertation and that, in my opinion, it is fully adequatein scope and quality as a dissertation for the degree of Doctor of Philosophy.
Mark Musen
I certify that I have read this dissertation and that, in my opinion, it is fully adequatein scope and quality as a dissertation for the degree of Doctor of Philosophy.
Byron Reeves
I certify that I have read this dissertation and that, in my opinion, it is fully adequatein scope and quality as a dissertation for the degree of Doctor of Philosophy.
Donald Roberts
Approved for the Stanford University Committee on Graduate Studies.
Patricia J. Gumport, Vice Provost Graduate Education
This signature page was generated electronically upon submission of this dissertation in electronic format. An original signed hard copy of the signature page is on file inUniversity Archives.
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Abstract Based on providing visual representation of all functions and key pieces of content,
What You See Is What You Get (WYSIWYG) is the current interface design
paradigm primarily used in personal computing machines. As we move into a world
where computing power continues to increase, and we choose to decrease the physical
size of our machines so that they will fit into our pockets, WYSIWYG will break.
This research agenda explores a paradigm shift, asking whether users of computing
machines can effectively complete tasks without this reliance on visual representation
of all functions and information. The two experiments described in this dissertation
seek to answer these questions: 1) do visual cues of information and function continue
to be required by users in order to complete tasks using mobile devices? 2) are users
moving beyond a reliance on recall and recognition memory in human-computer
interaction? Furthermore, if these experiments are successful in showing that users
no longer need to rely on visual cues in ways similar to the WYSIWYG interactions,
can we then describe human-mobile interaction within a memory framework beyond
standard recall and recognition?
We built two distinct task-based protocols in which participants were asked to
work through multi-step tasks, enacting functions and locating pieces of information
that we described as being located outside of the physical space of the screen. These
functions and pieces of information were not visually represented on the screen.
Rather, the participants were primed to understand that the functions and information
existed in this non-visual form and could be enacted through particular interaction
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techniques that referenced the particular, specific space outside of the screen where
these items “lived.”
In the two experiments, participants worked through tasks, either in a
WYSIWYG or in a YUMYS paradigm. We took a series of behavioral measurements,
including time on task, total number of interactions between the user and the machine
in order to complete the task, and successful, correct completion of the tasks. The
outcome of this research agenda indicate that the YUMYS interface paradigm will
provide a better design framework for mobile designers that will allow mobile users to
perceive a decreased workload and increased success as they complete tasks within a
YUMYS interface.
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Acknowledgements As the family lore goes, my grandfather received the first PhD conferred by The
University of Texas at Austin. The degree was in Philosophy. My mother followed in
his footsteps, starting a PhD program in Mathematics, also at The University of Texas
at Austin, before deciding one day she’d rather be at Barton Springs, buying a new
swimsuit, and switching over to work on a Master’s Degree in Philosophy. My
mother’s high school friend, Bob, who has become her companion later in life, also
received a PhD from The University of Texas at Austin, this one was in Government.
The additional degrees, and football titles, from UT Austin held by my family and
close friends are too numerous to mention here.
It is not just the institution that has made my PhD experience, and in particular
the dissertation writing process, vastly different from the experience of these
forerunners of mine. The acts of writing and research themselves are different. They
have been separated from physical location, in large part by the tools that support
those processes, and it is these tools that became the focus of my research efforts over
the last 6 years, both inside and outside of the academy.
Where my grandfather was tethered to a library building, and spent significant
time with physical books, I continue to get lost in my primary library—both the
physical building as well as the web of pages and paths that take me to resources and
references while I sit on my couch at home. Where my grandfather wrote his drafts
longhand, pencil on paper, primarily in the library, I draft on a machine whose power
is hard to compare to that pencil and paper. It weighs slightly less than 2 pounds,
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holds the equivalent of roughly 40,000 dissertations like mine or my grandfather’s,
and slips nicely out of my purse in flight so that I can edit in transit. My grandfather’s
dissertation was written in Austin. Mine has been written in Palo Alto, San Francisco,
San Jose (California and Costa Rica), Los Angeles, Tahoe, Reno, Dallas, Austin,
Atlanta, Washington, DC, New York City, Salt Lake City—and finally fine tuned
overlooking the waves in the Pacific Ocean in Central America.
My dissertation has been written on planes, on trains, in libraries, at diners, on
my couch, at my dining room table, at numerous friends’ dining room tables, on front
porches, in hammocks, while waiting for staff meetings, while selling movie tickets,
while checking in volunteers, in between yoga classes, after coming in from surfing,
listening to the Pacific ocean, looking into Squaw Valley, looking over the Stanford
oval, gazing out along Lake Austin, and in so many coffee shops that I’ve started to
consider my tip rent for office space. (I’m a bigger tipper now than ever.)
I am fortunate to have found a uniquely wonderful match in my dissertation
advisor, Cliff Nass. While he has his quirks—as we all do—his strengths as an
advisor matched very closely what I needed to be successful: ability to brainstorm
about anything, expressed excitement in my ideas, verbally articulated support and
reinforcement of my progress, ability and willingness to not just oversee but teach. As
needed, Cliff would pull out a pencil and paper and walk through a statistical concept
with me one-on-one until I understood and could describe it back to him. It wasn’t
just about clicking the right buttons in the software package of choice. In my career as
his student, he did this as early as the first lab meeting I attended and as recently as my
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final read through of my dissertation with him before I shared it with my full
committee.
I am fortunate to have found a willing advisor-in-spirit, just at the edge of
retiring, when I started the program. Don Roberts was the superstar academic name in
the Department of Communication at Stanford University with which I was most
familiar as I had been advised by his colleague Sandy Calvert during the previous two
years of Master’s levels studies at Georgetown University. Don was no longer taking
on students as primary adviser, but he was paying attention as I struggled through my
first two years at Stanford. After I returned from a full year’s leave of absence, Don
was only teaching in the winter quarter (which coincided nicely with NCAA
basketball). Our schedules barely overlapped, but they did so long enough for Don to
catch me one morning, sit me down, and say “when are you going to get out of here?
You need a plan.”
Byron Reeves, Mark Musen, and Ted Glasser all provided additional support.
No graduate student in our department would make it through without Susie Ementon.
Erina Dubois went the extra mile with cheer and panache and is someone I hope I get
to share a margarita with one day.
I am grateful to the CHIMe Lab, Cliff’s research group, which I joined upon
returning from that year’s leave and making a needed change in my academic career.
This group of talented, driven, fun, smart students allowed me to catch glimpses of
what I originally found so exciting about research work within an academic institution.
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Sincere thanks to Google for the Google Research Grant awarded to my work,
which freed up my academic time to push through on the dissertation. Sincere thanks
also to eBay, who provided me with a flexible schedule, a series of interesting
projects, opportunities to see research in industry, and a cheering squad that truly
wanted me to succeed. Special shout outs to Tori Lynn Bailey, Scott Joaquim,
Morgan Campbell, Rodney Tupai, John Bodine, Jenn Hill, Tanaya
Suveerachaimontian, and Tricia Clement. Cinequest, the best film festival you’ve
never head of, and Wanderlust, the yoga/music festival you’ll one day know, reminded
me to get outside of my head.
Remarkably, all 6 other members of my cohort are awesome, and we finished
up within 7 calendar years of starting, with various leaves along the way. Not only did
I enjoy their company, humor, and support, I am psyched that I will forever be
associated with Drs. Mike Ananny, Brent Bannon, Lori Gauthier, Laura Granka,
Shailo Rao, and Daniel Schneider.
Though not in my cohort, Seeta Gagandharan, Lise Marken, Phil Garland,
Leila Takayama, Erica Robles, Dan Kreiss, Victoria Groom, Mike Nowak, Abhay
Sukumaran, Dean Eckles, Helen Harris, Kathryn Segovia, Yph Lelkes, Sean
Westwood, Solomon Messing, Ethan Plaut…and I’m sure there are others I’m
forgetting…made my life better. (Special note to Destiny Lopez, spouse of Stanford
student Dan Kreiss, who offered to prepare food for my defense. A truly thoughtful
offer.)
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I am a lucky girl to have encountered the students I did. I was enriched
through my teaching experience, having a chance to work with talented, driven,
pleasant undergraduates. Many of the students who worked as my research assistants
did so while also serving the Stanford community as varsity athletes. These
individuals learned all the right lessons from being part of organized sports for nearly
their whole lives: they are eager, hard-working, have the ability to manage their time,
understand trade offs, work well in teams, are able to assess their own strengths and
weaknesses—and play to their own strengths and allow others to play to theirs—and
take critique as a way to learn and get better. There were many, but two stuck it out
with me for multiple years and deserve much more than this simple mention by name.
Thank you, James McGillicuddy and TJ Novak.
I had campus-based allies outside of my department, including Jim Sirianni,
Cory Potter, Eric Grant, and Meri Mohr from the Ed School. Miriam Kolar and
Jonathan Abel from the Center for Computer Research in Music and Acoustics gave
me the coolest academic research opportunity. I hope I’m not done collaborating with
either of them.
Washington, DC was pulling for me in the form of John Horrigan and the rest
of the crew at the Internet & American Life Project at the Pew Research Center who
hosted me for a summer internship when I hightailed it back east from California for a
little perspective after Year 1. Bill Shute and all the folks at The University of Texas
System Office for Federal Relations made sure I knew I always had a home to return
to. Zach Richter, Parag Mehta, Duane Pozza, and DeVere Kutscher made sure there
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were cookies, cocktails, stories, and clean sheets. Don and Julia Carlson and Bill and
Sharon Archer were proud of me no matter what. The Communication, Culture, and
Technology program at Georgetown University boosted me back into graduate work.
Clearly The University of Texas at Austin remains my First Academic Love.
Thank you John Daly and Jim Vick for consistent, enthusiastic, and heartfelt
cheerleading.
Pam Ng and Marcie Shelton are the two best non-roommate roommates I could
have, both motivating me to get off my ass to run or do yoga or otherwise aim to
something crazy that ultimately convinced me I could finish the dissertation. Paul and
Gloria DeVere gave me a place to stay in Austin every single time as well as all the
fried okra I wanted to eat. I cannot speak highly enough of the impact of the care
packages of flip flops, chocolate chip muffins, and cheering posters Gloria put
together. Liz Bandy inspired me with her continued self-reflection and aim to
greatness in research, writing, teaching, baking, shopping, and keeping me sane. Ben
Kutler offered direction and perspective and the occasional delivery of ice cream.
David Ames and Patricia Kuljian were my personal pit crew.
Allegedly there is a Mark Twain quote that describes San Francisco as a city
filled with adventurers, a place filled with people who moved west, hit the ocean, and
decided they better just stay put. I’ve found the greatest people here who’ve made my
life very full. They’re family in the best, strongest, and most resilient sense. If I had
the space, I’d tell you I love each of them and here’s why. For now, I’ll just list some
names: Eric Grant, Jason Nolan, Rocel Ryan, Krista Huerta, Helen Kuo, James
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Skelton, Romain Galoisy, Alan Becker, Mollie Thomas, Kimmy Brock, Dr. Mat
Brock, Nate Teisman, Kim Thompson, Skip Thompson, Tonya Zohba, Alex Makayev,
Chris Peterson, Heather Kastern, John Moran, John Cook, Lamont Lucas, William
Pietri, Jenn McGraw, and others. Meri is a rock solid, consistent, absurdity-
appreciating, fun, savvy friend. Lindsey infuses the world around her with unique
energy and is fiercely protective of the people she loves. I count on my quarterly
dinners with Leland to check in and be well. On the first night we had dinner together,
Reading listened with genuine interest as I explained that while the words of my
dissertation title worked, it was parameters that were important (gerund, preference for
dual meaning, inclusion of the colon). He didn’t automatically write me off as crazy
and has been making me laugh, and smile, ever since. I am honored to be the white,
female Arshad and pleased with the privilege and responsibility that come with that
title. Running a marathon convinced me I could write a dissertation. Angelique
convinced me I could run a marathon. Mike just got it when I needed someone to just
get it. Lauren, Rachel, Cathi, Anita, and Chrissy provided the antidote.
And finally a note on this work: it is clear to me that humans will continue to
be deeply connected to computing devices—perhaps not inevitably but very likely.
This slice of research examines ways to ease the translation between device and
human; as a research project, it was fun, fruitful, and scoped. The greater benefit of
the project to me is that it has motivated me to watch humans in their interactions with
one another, both mediated and unmediated, as well their avoidance of interactions
with others, often eased by a phone or iPod or other device. What drew me to the
study of the discipline of Communication was the necessary location of
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communication in connection made among humans. It can be difficult enough to find
connection between two humans with no mitigating factors. Adding in additional
people as well as the increasing number of ways that we can be in touch with one
another—face to face, phone, email, SMS, text chat, voice chat, video chat, postcards,
Twitter, Facebook, and the still coming brand names that will become synonymous
with subtly different interaction channels—makes this originally simple equation a
combinatorial explosion problem. I’ll never be bored.
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Table of Contents Abstract.......................................................................................................................... iv
Acknowledgements .......................................................................................................vi
Table of Contents ........................................................................................................xiv
Chapter 1: Introduction................................................................................................... 1
Chapter 2: Mobile Devices............................................................................................. 3
A Short History of the Development of the Mobile Device ...................................................3
Chapter 3: Command Line, Recall Memory, & Computing Machines.......................... 7
Command Line Interface ........................................................................................................7
Recall Memory .......................................................................................................................8
Chapter 4: WYSIWYG, Recognition Memory & Computing Machines..................... 10
WYSIWYG Interface ...........................................................................................................10
Recognition Memory ............................................................................................................10
Chapter 5: Problems in Mobile Usability..................................................................... 12
Design Challenge: Small Screen Size...................................................................................15
Design Challenge: Cumbersome Input Mechanism .............................................................21
Chapter 6: YUMYS, Enactive Memory, & Computing Machines .............................. 28
Chapter 7: Research Agenda ........................................................................................ 31
Chapter 8: Experiment 1- Introduction......................................................................... 33
Chapter 9: Experiment 1- Method................................................................................ 34
Abstract .................................................................................................................................34
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Overview of Design ..............................................................................................................34
Participants............................................................................................................................35
Materials & Equipment.........................................................................................................35
Procedure ..............................................................................................................................36
Interaction Type ....................................................................................................................37
Measures ...............................................................................................................................38
Chapter 10: Experiment 1- Results............................................................................... 42
Behavioral Effects.................................................................................................................42
Attitudinal Effects: Positive Affect Negative Scale (PANAS).............................................44
Attitudinal Effects: Semantic Differential (Interface) ..........................................................48
Attitudinal Effects: Semantic Differential (Device) .............................................................50
Chapter 11: Experiment 1- Discussion......................................................................... 54
Chapter 12: Experiment 2- Introduction....................................................................... 57
Chapter 13: Experiment 2 - Method............................................................................. 58
Overview of Design ..............................................................................................................58
Participants............................................................................................................................59
Materials & Equipment.........................................................................................................59
Procedure ..............................................................................................................................60
Task Type .............................................................................................................................63
Measures ...............................................................................................................................64
Chapter 14: Experiment 2- Results............................................................................... 70
Results Overview ..................................................................................................................70
Content Task .........................................................................................................................70
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Map Task ..............................................................................................................................75
Overall Assessment: Attitudinal Measures...........................................................................85
Attitudinal Effects: Semantic Differential (Interface) ..........................................................86
Attitudinal Effects: Semantic Differential (Device) .............................................................87
Attitudinal Effects:PANAS...................................................................................................88
Chapter 15: Experiment 2- Discussion......................................................................... 94
Chapter 16: Conclusion ................................................................................................ 98
Appendix 1.1—Experiment 1 Protocol ........................................................................ 99
Appendix 1.2—Correlations, Dependent Variables................................................... 116
Appendix 2.1— Experiment 2 Researcher Checklist................................................. 122
Appendix 2.2— Experiment 2 Script (YUMYS Condition) ...................................... 124
Appendix 2.3— Experiment 2 Participant Documents .............................................. 129
Appendix 2.4— Correlations, Dependent Variables.................................................. 146
References .................................................................................................................. 148
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1
Chapter 1: Introduction This dissertation seeks to answer the following question: can users effectively
complete tasks on a computing machine in which the interface has been designed
within the You Use More than You See interface paradigm? The YUMYS interface
paradigm is an evolution beyond the What You See Is What You Get (WYSIWYG)
interface paradigm, in which all functions and information are visually represented for
the users to choose from. The YUMYS paradigm makes use of the space outside of
the screen, as well as the user’s enactive memory and a larger mental model of the
interface, in order to locate key functions and pieces of information outside of the
visual range of the screen. This is a vital step in interface design as devices get
smaller and computing power increases. We will continue to want to do more and
more with a smaller device. There will no longer be the screen space available in
order to visually represent all functions and information.
Chapter 2 begins with a discussion of the mobile device. Indeed it is this
machine that requires that designers move past WYSIWYG as a design guideline.
This chapter provides the basic outline of the story of the mobile device, describing
the development of the mobile phone, the Personal Digital Assistant (PDA), and their
eventual convergence.
Chapters 3-4 provide some background into previous interface design
paradigms—specifically the command line prompt and the aforementioned
WYSIWYG paradigm. These paradigms are described briefly and connected with
recall and recognition memory, respectively.
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Chapter 5 returns to the mobile device and outlines research conducted in this
environment that has resulted in repeated findings that point to two major
considerations when designing for a mobile interface: 1) the small screen problem;
and 2) cumbersome input mechanism.
Chapter 6 then returns to the thread of the evolution of the interface paradigm
and proposes that, at this moment, a paradigm shift is called for. This chapter
describes the You Use More than You See (YUMYS) interface paradigm. And
similar to command line and WYSIWYG, YUMYS also connects to a particular
memory process—enactive memory—which is described in this chapter as well.
Chapter 7 then turns to the bulk of the dissertation, describing the research
agenda that guided the empirical work undertaken to answer the question of whether
users can effectively complete tasks on a computing machine that does not visually
represent all functions and information. Chapters 8-11 describe Experiment 1, in
which we had participants complete tasks within the YUMYS interface paradigm.
Chapters 12-15 describe Experiment 2, in which we compared the efficiency of
participants’ completion of tasks in a direct competition between YUMYS and
WYSIWYG. Chapter 16 provides a short summary of the work and recommends
future direction.
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Chapter 2: Mobile Devices It is no longer the case that we must prepare for shopping trips in advance or arrange a
pre-determined location to meet up with friends. Where once a trip to the library, or
eventually a visit to a stationary computer, was necessary to retrieve information, we
now have access via devices that travel with us. We have developed into beings
where “much of our information need is generated on the road, while shopping stores,
or in conversation. Frequently, we know that the information we need is
online…PDAs are, in principle, a perfect medium for filling such information needs
right when they arise” (Buyukkokten,Garcia‐Molina,&Paepcke, 2000).
A Short History of the Development of the Mobile Device According to the tracking survey conducted by the Pew Internet & American Life
Project, 85% of Americans reported having cell phones in April 2009. (The Pew
Internet & American Life Project tracks these numbers several times a year through a
random digit dial survey. Data sets can be found here:
http://www.pewinternet.org/Data-Tools.aspx.) This is particularly notable when one
considers that, although the first lab-tested cell phones were in production in the
1970s, the first commercially available cell phones did not appear until the 1990s. In
less than 2 decades, the cell phone market has come close to saturation. Additionally,
factors unique to the mobile device market make the pervasive adoption of these
devices worldwide more likely than the desktop and laptop computers.
The earliest versions of mobile devices were simply phones that did not rely on
a physical cable to transmit sound waves from sender to receiver. Because they relied
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on cellular technology, it became possible for an individual to carry a phone with him
throughout his day. Relative to today’s models, the first mobile phones were big and
clunky. These devices were the direct progeny of the landline telephone and before
that the telegraph. At the time, these tools were real-world instantiations of the
transmission theory of communication, which modeled information traveling from
sender to receiver. (Weaver & Shannon, 1963; Carey, 1989) But they lacked many of
the additional functions we expect in our mobile devices today.
A concurrent thread was also developing in the early 1990s. The first Personal
Digital Assistant, or “PDA,” was introduced at the 1992 Consumer Electronics Show.
This annual tradeshow has become the launch pad for all (non-Macintosh) personal
electronics that companies are seeking to market to individuals rather than to
businesses. PDAs were first introduced in the early-mid 1990s and were marketed to
help people keep track of their calendars, contacts, and to-do lists all in a single, small,
highly portable computer. The success of these early devices indicated that “users are
willing to put up with small, hard-to-read displays, limited storage and battery life,
slow CPU speeds and cumbersome data transfer, in the hope of achieving truly
portable access to electronic data” (Kamba, 1996). It was marketed as a device that
could allow an individual to carry all the coordination documents she once kept in
physical form in one location. The physical calendar, personal address book, and
notepads were no longer necessary. The PDA facilitated these tasks throughout the
day.
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Over time these two devices, the mobile phone and the PDA, merged. Rather
than keep a separate cell phone and personal digital assistant, an individual could carry
one mobile device that included applications for updating a calendar, maintaining a
personal address book, and making a call. The phone ceased to be a device unto itself
and became rather just another application on a device increasingly used to keep track
of one’s life.
An additional important thread of technology development during this period
was the expansion of the Internet and its widened availability for personal use.
Increasingly, any device with a computing brain could join this network of computing
devices. The merged device, a small computing machine with a phone application,
was able to join this network. While the user of such a device was able to make a
phone call, he also had unprecedented access to stores of information through that
same mobile device.
Mobile devices have evolved beyond simple mobile phones; they are
equipment that support our consumption habits, entertainment desires, and our
interactions with others. The continuing development of the device, the network, the
consumers, and the producers has led to an environment in which these devices are not
brought out for only unusual or niche moments. Their development has been
influenced not just by the personal computer, but also the landline telephone, the
physical library, the television, the radio, and myriad other traditional media that have
provided information and entertainment into our lives. They are intertwined with
communication and data storage networks. “Two centuries of rapid technological
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advances and innovation have evolved communications and commerce from being
tied to networks of waterways and (literally) horsepower to being tied to digital
communications networks” (Venkatesh, Ramesh, & Massey, 2003). The
pervasiveness of the mobile device has further negated the vitality of the physical, in-
person connection, continuing the tradition of devices that shared messages across
space more quickly than a person could travel. But while these devices have found
great prominence in contemporary society, there has been considerable work needed
to provide a user experience that allows an ease of integration. This has been
developing at the individual level with great attention paid to the human-mobile
device interaction as an evolution of human-computer interaction. Key to this work is
the interface.
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Chapter 3: Command Line, Recall Memory, & Computing Machines
The interface is “software that shapes interaction between user and computer”
(Johnson, 1997). It is what the user sees and manipulates on the screen in order to
enact a particular task using that machine and receive an expected outcome. The
interface is one part of the translation process that turns a user’s desire of what the
machine should do into an outcome that the machine has done.
The majority of present day interfaces on mobile devices are graphical in
nature. Though they show up both in pictures and in words, they are a step forward
from traditional text-only command line methods of interacting with computing
machines.
Command Line Interface The command line interface requires that the user recall a list of text instructions to be
given to the machine in order to receive expected results. Command line interfaces
were commonly used in mainframe systems and early personal computer systems,
before graphics technology developed to a level that allowed for alternate interface
versions.
Commonly a user would type code words using an attached keyboard. Upon
the user’s submission of each instruction individually, the computing machine would
translate and react to the input. While computer users now primarily interact with
their computers via graphical user interfaces (“GUIs”), there are still instances in
which users revert to command line prompts in order to work with machines. For
instance, any PC user can bring up a command line pane on his Windows-running PC
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by clicking on the start menu in the bottom left hand corner and then selecting “run.”
In the subsequent window, the user types in “cmd.” This then launches a window in
which the user can interact with the machine in traditional command line form.
Recall Memory The command line interface relied primarily on “recall memory.” Individuals rely on
recall memory when remembering a piece of information without the provision of any
link or aid in the memory process. This stands in contrast to “recognition memory,”
during which memory process the individual is given a cue, primarily visual or aural,
that connects the individual to the piece of information he seeks.
More than a century ago, Hermann Ebbinghaus (1913) first published his
studies on how time affected recall abilities. Some of the earliest research were simple
memory tests, in which the participant would memorize a set of letters and then wait
periods of time to see how the lag affected his ability to recall the set of letters. It
became clear that time did affect recall memory detrimentally. As seems obvious to
us now, Ebbinghaus found that his ability to remember these letters declined as time
passed. In his continued research agenda, Ebbinghaus refined this earliest outcome,
finding that participants were more likely to be able to remember something through
free recall the higher their interest in the subject and the more attention they had paid
to the subject during the treatment.
In continued research, Ebbinghaus (1913) found that type of content affected
an individual’s ability to remember the content in question. For instance, he found
that people could more easily remember the words to a song rather than the words to a
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speech. In this finding, the concept of “cued recall” began to be teased apart from
“free recall.” The melody of the song intertwined with the words, allowing the
individual in question to elaborate the words from the melody in the instance of
recalling song lyrics.
Recall memory requires that the user pull a skill, piece of information, or
knowledge up without being given a reminder or link to enable that. In the instance of
command line interfaces, the commands themselves were stored in such a way as to
require their recall.
One could argue that the commands used in the command line human-
computer interaction had some inherent cue in that similar formatting and clues were
used in sets of commands. Thus the commands were not expected to be simply freely
recalled but were in part cued with associated information.
Recall memory has been a focus of interest for subsequent interface designers.
Relying on recall memory on the part of the user requires a greater effort on the part of
the user. To the extent that designers are able to support recognition rather than recall,
the user will better be more likely to integrate a new device or piece of software into
his life. However, text-based systems, such as command line interfaces, relied on
recall memory.
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Chapter 4: WYSIWYG, Recognition Memory & Computing Machines
While command line interfaces are used in some instances in contemporary
computing, today’s personal computer interfaces are primarily graphical in nature,
which has allowed for greater use of these devices by a larger number of people in a
greater variety of contexts.
WYSIWYG Interface Designers tend to work within the framework of What You See Is What You Get or
WYSIWYG. The WYSIWYG context developed alongside more elegant graphics
options, thus allowing designers to incorporate visual representations of tasks and
information. At the same time, mouse pointers were developed that allowed the user
to point to and click on these visual representations in order to instruct the computing
machine.
Recognition Memory The WYSIWYG context allows the user to rely on recognition rather than recall
memory by providing extensive visual cues throughout an interaction between human
and machine.
Recognition memory relies on cues that activate the memory in a user. The
canonical example is the multiple choice test. From the student’s perspective, in
answering a multiple choice question, she is not required to actively pull an answer
from her memory. Rather, she reviews the list of possible answers that is available to
her, and she chooses from that list. Ideally, one of the options will activate the
memory that she has about the material, allowing her to select the correct answer.
11
Conversely, when a student responds to an essay question, he must pull the entirety of
the answer from his memory, with no cues available to him in order to activate the
location in his memory where that material resides.
WYSIWYG makes use of this concept of recognition, which decreases the
effort required on the part of the user to interact with and integrate a device into his
life.
12
Chapter 5: Problems in Mobile Usability Neither the command line interface nor WYSIWYG provides an optimal framework
for designers creating interfaces in a mobile environment. Several obvious design
constraints have been noted and researched in the mobile space that break both of
these paradigms.
As designers, programmers, product managers, and marketers can attest, the
initial excitement surrounding introductions of new technology carries tools only so
far into widespread use. While innovators and early adopters may be willing to work
with imperfect tools, the general population expects more, particularly from these
mobile devices that are sold at a price point that makes them more than a simple
everyday purchase. Even if other factors are in place—network, price, speed,
perceived need—eventually providers must focus on the ease with which a user can
learn a new tool and subsequently incorporate it into her life.
There has been a great variety of user experience in the history of pocket
devices. The earliest examples included “monochrome portable displays for
scheduling and address books” (Khella & Bederson, 2004). These early devices were
clunky and sometimes required technical knowledge beyond the scope of the everyday
person in order to troubleshoot problems that stood in the way of users accomplishing
their tasks. More recently, however, Apple’s iPhone has set a standard that is both
beautiful and easy to use. This device looks good, is easily learnable, highly portable,
and supports many functions. Many give great credit to Apple’s focus on appealing to
the user both through “cool factor” as well as through extreme focus on usability.
13
Indeed “an important prerequisite for the success of e-commerce and m-commerce
sites is ensuring that customers’ experience, via the interface, satisfies both their
sensory and functional needs” (Venkatesh, Ramesh, & Massey, 2003).
The focus on the incorporation of tools into or the effect of technology on a
human’s life is not new, and it is not limited to the integration of computing
machinery into human life. Ergonomics professionals help manufacturers create
chairs that mirror the spine, keyboards that sit at an angle, and kitchen utensils that
actually fit directly into the contours of the hand.
The practice of usability in technology has grown directly out of these trends—
with applications to both hardware and software. Hardware manufacturers employ
researchers to observe and report how devices are actually situated in home and office
contexts and carried from place to place. Software and Web companies maintain user
experience research teams to watch users as they attempt to complete tasks. These
experts note when the actual user path deviates from the expected one, and they then
make recommendations back to development teams about how to update the site in
order to better support the actual user path.
Mobile devices and networks pose “new challenges and questions. While
mobile phones and PDAs can provide access to an array of new applications, they
impose limitations such as small screen size, limited screen resolution, and
cumbersome input mechanisms” (Venkatesh, Ramesh, & Massey, 2003). These
particular limitations have become the focus of a great deal of work, in which
designers and researchers have tried to provide new innovations given these
14
parameters and then sought to understand the subsequent effects. While lessons can
be learned from the usability findings of earlier computing machines, “the mobile
experience is fundamentally a different use case. The experience is largely about
saving time, varying locations, and convenience” (Venkatesh, Ramesh, & Massey,
2003).
Venkatesh’s two noted limitations, small screen size and cumbersome input
mechanisms, have provided rich ground for designers to innovate. Screen size is an
obvious limiting factor. The physical screen can be no larger than the device itself,
and a major benefit of the device is the opportunity for us to fit it into a pocket. Thus
designers must innovate on methods to most efficiently use this space. It is not simply
a matter of infinitely reducing what is displayed on desktop monitors.
Mobile devices also make use of input mechanisms that are distinct from older
desktop machines. Earliest modes of interacting with these mobile devices included
complicated series of button-pushing and touching the screen itself with a stylus.
More recent implementations make use of “multi-touch,” a method of directly
manipulating items on a screen with one or two fingers. With each input
development, device users have had to learn a new movement. Adoption of the device
is ultimately dependent on an individual being able to communicate to the device what
task she would like to complete.
In seeking to understand how these design limitations affect an individual’s
ability and willingness to use a mobile device, researchers are also implicitly affirming
their own views of whether they believe the device to be a tool or an extension of the
15
self. The following sections provide an overview of exemplary studies done to
understand how to best design for improved mobile usability given the constraints of
1) small screen size, and 2) cumbersome input mechanism. These studies are
presented in categories that also reveal the research assumption of whether the device
is a tool or an extension of the self.
Design Challenge: Small Screen Size The question of screen size has been an obvious priority for designers and researchers
of mobile devices. Lessons from desktop machines could only go so far in providing
answers for mobile devices. When a user works on a large display with reasonable
resolution, it is not uncommon that there is more real estate than is needed for all the
active tasks that the average user is working with at any given time. Designers
working with desktop monitors have been able to rely on simply placing indicators on
the screen itself to remind users what information or functions are available to them.
This is a necessary condition for the What-You-See-Is-What-You-Get, or
WYSIWYG, interface. The WYSIWYG context allows the user to rely on recognition
rather than recall memory by providing extensive visual cues throughout an interaction
between human and machine.
However, WYSIWYG is less useful when the screen size is reduced
dramatically. This can particularly be seen in studies that have looked at how
individuals consume Web content on their mobile devices. Some attempts have
continued to try to incorporate WYSIWYG ideas into the mobile context. These
16
studies assume that the user is turning to the device in order to accomplish the task of
finding out a piece of information through reading.
Early attempts to provide readable content on a very small screen relied on
rearranging the content itself in various ways since the problem cannot be alleviated
simply by reducing the size of the font infinitely. “Changes in PDAs are limited by
two constraining factors: the dimensions of displayed text and of the screens on which
the text is displayed are unlikely to change very much. Reductions in the size of the
displayed text will be limited by the ability of users to discern small type sizes on any
display device, especially one of relatively low resolution” (Kamba et al., 1996).
Many Web sites rely both on an instantiation of the page that displays it in an aesthetic
manner for regular desktop displays as well as an adapted one for mobile devices as
well.
An early method of effectively displaying content in a mobile environment
involved making use of text summarization for web browsing. Members of the Digital
Libraries Lab at Stanford looked at “five methods for summarizing parts of Web pages
on handheld devices, such as personal digital assistants (PDAs) or cellular phones.
Each Web page is broken into text units that can each be hidden, partially displayed,
made fully visible, or summarized” (Buyukkokten,Garcia‐Molina,&Paepcke,
2000).
Another attempt at content display manipulation was shown in the Pocket
PhotoMesa project (Khella & Bederson, 2004). This project made use of the
Zoomable User Interface, the ZUI. “Ideally, a ZUI renders information space into a
17
single screen allowing users to get an overview about the information domain,
identifying themes and patterns for later interaction” (Khella & Bederson, 2004). The
team found that individuals were able to learn and make use of this new way of
interacting with the device.
Other methods of displaying content have been the single-column view and the
thumbnail view. In the single column view, all content on a page is squeezed into a
single column that is displayed length-wise on a mobile device. While this allows for
all content on a page to be displayed at once, thus decreasing the number of clicks on
the part of the user, it does require extensive scrolling. It also alters the look of the
page significantly enough that it may be unrecognizable.
The thumbnail view corrects for this latter problem but may reduce the size of
the page so much that the text is unreadable. One set of researchers have combined
these two methods to create and test a version they call “summary thumbnails—
thumbnail views enhanced with readable text fragments” (Lam & Baudisch, 2005).
There was considerable success in this attempt. Results from both a qualitative and
quantitative user study indicate that there was a “strong participant preference for the
Summary Thumbnail interface over the Single-column and the Thumbnail interfaces
on small screens when browsing web pages originally designed for the desktop” (Lam
& Baudisch, 2005).
Others have wrangled with the display problem with maps and directions,
another case in which the user is turning to the device as a tool in order to accomplish
a particular task. Designers in the mobile space have attempted to satisfy both the
18
requirement of seeing the whole route as well as being able to zoom in on the detailed
step-by-step directions in a number of ways. Some take the strategy of showing two
views that can be toggled back and forth. The idea of the “viewport” captures this
idea. “Viewports into large visual workspaces are sometimes supplemented by a
separate window that displays a miniaturized overview of the entire workspace” (Cox
et al., 1998). The user can work within the window that allows for control over the
detailed task but can also select out of that window and back into the overview
window when the user needs a reminder of the larger context at hand.
Cox et al. (1998) wanted to look at alternatives to the separate window solution
and considered whether users could effectively work with transparent layers. Rather
than asking the users to toggle between two separate opaque windows that necessarily
completely block the view of the other window, these researchers “layered a
transparent version of the overview atop the viewport” (Cox et al., 1998). Technically
the user could then actively work on the document in either window but would always
be able to see the information provided in the secondary window without having to
activate that window. The team conducted a usability study on this design to assess
whether users could work within this context, and they found that “people were able to
comprehend and successfully use this unusual system to their advantage…transparent
overviews overlaid atop full-scale viewports proved useful, in spite of it being an
unusual way of working” (Cox et al., 1998).
Sarkar et al. (1993) “propose the metaphor of rubber sheet stretching for
viewing large and complex layouts within small display areas.” In this context, any
19
content that is displayed on a screen can be enlarged in the way an image emblazoned
onto a rubber sheet would be enlarged: by grasping the sides of the sheet and
stretching it until the image gets to a desired size. This team focused on the problem
of providing context and detail but in a way that was different from the more
traditional method of showing a detailed, zoomed in portion of a larger display. With
the rubber sheet, users can choose to “stretch” just a portion of the screen, effectively
leaving the larger context semi-intact while being able to focus in on a chosen area.
The designers argue the benefits of this program are its “intuitive interface…(the fact
that) it can respond in real time…(and its) smooth integration of focus and context”
(Sarkar et al., 1993).
It is clear that the designers in these instances were still trying to make use of
the WYSIWYG ideals. Designers feel that information must be somehow visually
represented so that the user may be reminded of its presence.
Other designers have assumed that not all information related to a task must be
visually represented on the screen of the device itself. In these instances, the designer
may assume that some knowledge can be stored within the human for use on the
device rather than relying on visual memory cues positioned on the interface that
indicate to the user how she is to use the device.
Staffan Björk and his team (2000) showed evidence of these assumptions in
their write up on “PowerView,” an application that “shows how non-standard
graphical user interfaces, together with the introduction of links between data of
different types, can ease the interaction with digital information on small mobile
20
devices.” The interaction is based on flip-zooming, in which several areas of focus are
presented visually, and the user selects which one to focus on at any given instant.
Their small user study indicated that users are highly adaptable to new systems—even
in instances in which the new system is not modeled directly after legacies. Their
“evaluation showed that the system can be self-taught in the same time as the
Windows CE interface, even though the system does not build upon an already well-
known user interface” (Björk et al., 2000).
Baudisch and Rosenholtz (2003) also showed somewhat elevated expectations
of their users’ abilities to be aware of content that is outside of the space of the screen
itself. Their Halo project focused on the use case of viewing maps on a device. But
where Cox and his team made use of transparent layers to still show all information on
the screen itself, Baudisch and Rosenholtz allow vital pieces of content to remain
outside of the screen, with a simple visual cue, or halo, reaching just into the physical
screen to be displayed as a reminder that there is something outside of the displayed
map that may be important to the user. The designers posited that users needed clues
that something lay on the map outside of the visible portion; they believed that users
could learn the visual indication of visible rings pointing to their unseen antecedents;
and they relied on the user’s memory of what that antecedent is rather than holding
that information somehow in the visual cue.
Another interface variation was introduced in 1992 when Mander, Salomon,
and Wong reported to the Association of Computing Machinery Special Interest
Group in Computer-Human Interaction in 1992, a small user study conducted at Apple
21
Computer, Inc. This study explored the idea of applying a ‘pile’ metaphor from the
physical world of information storage, organization, and retrieval, as exemplified by
an office, to an electronic world of information storage, organization, and retrieval, as
prototyped onto computers. As a result of observation and interviews, the team
proposed that “incorporating ‘piles’ within a graphical user interface could provide a
number of interesting possibilities…piling requires less mental effort (and) convey(s)
a certain degree of imprecision in the suggested organization” (Mander, Salomon, &
Wong, 1992). This is in contrast to the stricter, more hierarchical structure of files and
folders that are most commonly used in personal computing.
A team from Stanford (Wang, Hsieh, & Paepcke, 2005) combined this idea of
making use of the space outside of the physical screen along with the “pile” metaphor,
In the Stanford project, users were able to create piles of documents, but they were not
required to locate them visually on the screen but could rather indicate that the piles
reside just outside of the screen on any of the four sides. Users could access these
piles by indicating with a stylus toward the location of the pile.
Design Challenge: Cumbersome Input Mechanism Aside from screen size, methods of input have been an important consideration for
designers in the mobile space. Interactions with these small devices differ necessarily
from interactions with standard desktop machines. Where the desktop machine makes
use of full-sized keyboards and mice/tracking pad accessories, the mobile device has
relied on touch screens, stylus interactions, and keyboards that require that keys
22
represent multiple symbols. Again we can see that much of this work is informed by
the assumption that individuals need a visual clue.
In most standard interface paradigms, a portion of screen real estate is devoted
to task interactions or commands that the user may give to the machine. While there
are methods by which the user does not have to follow the path outlined visibly on the
screen, most notably through the use of short cut key commands, these commands are
often duplicated on the screen as well. For instance, if a user using Microsoft Word
on a PC wants to save her document, she may do so by taking her cursor to the file
menu in the top left hand corner of the screen. When she clicks on “file,” a menu
drops down, occluding a portion of the document. She must then pull the cursor down
the menu and click on “Save.” It is not necessary that the user block part of her screen
in order to save the document, however. This command has a corollary via short cut
keys wherein the user can simply press the “control” and “S” keys at the same time,
performing the function of saving the document.
Replicating these traditional methods of interaction on a mobile device would
not work, but lessons learned from the short-cut keys can inform human-mobile
interaction. Designers have also turned to as-yet-unused methods of interacting.
One method of enhanced interaction makes use of so-called sonically enhanced
buttons. “The underlying hypothesis being that presenting information about the
buttons in sound would increase their usability and allow their size to be reduced.”
(Brewster, 2002) In this experiment, researchers hypothesized that on-screen buttons
could be made visually smaller if they were paired with information about the button
23
conveyed through a sound to the user. This project has mixed results showing that
“sounds significantly improved usability for both standard and small buttons—more
data could be entered with sonically enhanced buttons and subjective workload
reduced” (Brewster, 2002).
Marking menus have also emerged as a possible interactive technique by
which to speed task. “A marking menu is designed to allow a user to perform a menu
selection by either popping-up a radial (or pie) menu, or by making a straight mark in
the direction of the desired menu item without popping-up the menu (Kurtenbach &
Buxton, 1994). This stands in contrast to the hierarchical, linear menus that are
common as seen in widely used software such as the Microsoft Office suite of
products. Marking menus have been implemented in commercially available, but
rather niche, software. In the instance of Kurtenbach and Buxton’s 1994 paper at CHI,
User Learning and Performance with Marking Menus, an application named ConEd
was used as the basis for the user experiments. ConEd’s marking menu included the
six most used commands. If a user wishes to enact any of these tasks, he simply has to
press the stylus to the screen for a pre-determined length of time until the radial menu
appears. This circle is then divided into six equal pie pieces, each labeled with one of
the most frequent commands. The user must then drag the tip of the stylus over the
pie piece that corresponds with the command he wishes to enact. The authors were
curious as to whether such an interaction was a usable alternative to traditional menus
as well as whether they truly allowed for more efficient interactions. They had three
important findings: 1) that marking menus could be used in appropriate context; 2)
that users’ comfort with marking menus increased over time; and 3) that a user’s
24
ability to switch back and forth between marking menus and other interaction styles
was important.
Additionally mobile designers can look to the work done in physically
stationary but virtually 3-D environments. Using mobile devices while moving
through the physical world is the ultimate manifestation of what many virtual 3-D
environments are pointing to. In this way, projects such as the Infocockpit and other
3D environments (Tan et al, 2003) can inform good mobile design. While what was
displayed in these 3D environments was controlled by the research team, which is
specifically different from allowing users to wander through the physical world, the
lessons that came out can be applied. Specifically, Tan’s team found in their study
that “there is a significant performance advantage for users navigating through 3D
environments when optical flow cues are present” (Tan,Czerwinski,&Robertson
2003).Mobile designers may find that they need to allocate screen or device space to
visual cues that can stand in for larger tasks.
Command-line environments to WYSIWYG environments show the step from
memory to sight. Brewster’s sonically enhanced buttons show the possibility of
incorporating other senses as well. “It is suggested here that the advantages of
sonically-enhanced buttons in the desktop could apply to mobile devices and therefore
improve usability. The problems with button interactions are made worse by small
buttons and, because their screens are small, these occur often on mobile computers”
(Brewster, 2002). Although the small, sonically enhanced buttons did not show better
performance in the users than traditionally sized, non-sonically enhanced buttons did,
25
the project nonetheless provides evidence that designers are continuing to attempt to
link the machine closer to the human through a variety of senses.
Brewster’s (2002) work clearly strives to understand the opportunities for
incorporating a reliance on senses other than sight. In his work, sound provides
additional information about the interaction. However, sight remains key to knowing
exactly where the sonically-enhanced buttons are located on the screen; additionally,
the results of this study indicated that sight was essential in that participants perceived
greater workload and were less successful in their assigned task when the buttons
themselves were partially obscured from sight by the input device.
Furthermore Brewster’s work brings up the idea that individuals may be able
to communicate with their devices in a variety of ways. Command-line interactions
relied on memory; WYSIWYG relied on being able to see the screen. But to what
extent is vision essential to a human’s interaction with her computing machine? Is it
necessary that an individual actually see the screen in order to interact effectively? Or
can we rely on other senses and still receive the expected effects from the computer in
question? This question has not been central to mainstream work done in human-
computer interaction. Aside from work done explicitly to understand the experiences
of those who are vision-impaired, researchers of human-computer interaction have
often assumed sight in their manipulations. For instance, even though in their initial
work on using piles as a metaphor for desktop design, Mander, Salomon, and Wong
(1992) “explored gestural inputs as a way to invoke other browsing methods,” they
nonetheless wove in sight as a prerequisite for evaluating the system as a whole.
26
Participants were asked to assess in what form they most liked seeing the resulting
information, and the result showed a bias towards reliance on sight. “In general, users
thought they would make use of the ‘spread out’ view. Since all items were visible at
once, it supported recognition and comparison…They liked the idea of receiving all
incoming information in a pile which could be accessed with the viewing cone”
(Mander, Salomon, and Wong, 1992). Interestingly, however, the respondents also
went on to indicate that “they would want the system to prioritize items using
characteristics such as sender, topic, content keywords, date, and urgency.” (Mander,
Salomon, and Wong, 1992) This work of the computer can be fully pulled away from
the sense of sight, relying on the machine to do work for us that it is not necessary for
us to see.
Additionally, while we can rely on sight to support our making of gestural
inputs, it is also possible to rely purely on the movement of the appendage making the
gesture—the easiest case being the hand either touching the screen directly through a
finger, indirectly through a stylus, or indirectly mapped through a mouse movement.
Tactile feedback can improve such experiences. Physical keyboards are an excellent
example of an interactive mechanism providing tactile feedback. The key depresses
when touched—it actually moves physically in space—and then rebounds when
released. At the same time, the corresponding character appears on the screen. In this
way, feedback of success is provided through multiple sensory inputs.
Brewster (2002) noted that “one problem when selecting items with a stylus is
that there is no tactile feedback. With keys on a normal keyboard you can feel that
27
you have pressed them, with a stylus or finger on a touch screen it is hard to know if
you have hit the target item or not.” His solution was the sonic response. These
studies indicate that designers are starting to consider that the methods by which
humans communicate with devices may happen in a variety of ways.
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Chapter 6: YUMYS, Enactive Memory, & Computing Machines
Designing for the mobile interface has provided new challenges. The
questions of small screen size and cumbersome input mechanism have been priorities
for designers and researchers of mobile devices. WYSIWYG lessons from desktop
machines could only go so far in providing answers for mobile devices. When a user
is working on a large display with reasonable resolution, it is not uncommon that there
is more real estate than is needed for the active tasks that the average user is working
with at any given time. Designers working with desktop monitors have been able to
work within the WYSIWYG interface paradigm.
However, mobile interface designers have needed a new interface paradigm.
This dissertation recommends the You Use More than You See (“YUMYS”) interface
paradigm. YUMYS makes use of the best lessons learned from years of WYSIWYG
use, applying and adapting these forward to a mobile device interface.
As noted, two primary problems have been identified in mobile device
interface design: 1) the small screen problem and 2) cumbersome input mechanism.
The YUMYS interface paradigm seeks to solve both of these problems.
While the WYSIWYG interface paradigm relied on visual representation of all
information and tasks, the YUMYS interface paradigm seeks to push some of this
outside of the space of the screen. It is predicated on the belief that there are tasks that
have become rote in our use of computing machines that is it no longer necessary to
visually represent, or cue, them in our memory.
29
One such example is the “trash bin” on a laptop. In the WYSIWYG interface
used on an Apple machine, the trash bin is, by default, located in the bottom right
corner of the screen. Whenever a user wishes to enact the task of deleting a document,
she must simply drag it to the bottom right corner of the screen. Thus it is not
necessary to represent the trash bin visually; this space could be freed up for
something else.
In this instance, the user does not need to rely on recognition memory in order
to know where the trash bin is on the screen. However, it is not simply about a return
to recall memory—as was necessary in the days of command line interfaces. Rather
there is an evolution of the human-computer communication, in which the user is
relying neither on recall or recognition memory but rather on enactive memory.
Enactive memory is a component noted in social cognitive theory. (Bandura,
1986) Commonly connected with trial-and-error learning, enactive memory
encompasses the knowledge an individual keeps in the body after repeated exposure to
a movement. It is the memory that athletes rely on in order to respond within active
play situations. A tennis player can certainly articulate the components of a tennis
game—forehand, backhand, lob, smash, and so forth—but it is not this articulated
knowledge that allows her to respond with the appropriate stroke in the midst of a
match when the ball is returned by her opponent. It is enactive memory that allows for
this.
This framework applies to other areas in which repetitious movements or
gestures are common—such as working with computers or mobile devices. Consider
30
the example of the user who wishes to enact the task of deleting a document from her
machine. When asked where the trash bin is located, she may subconsciously swipe
her hand down and to the right to enact the task of moving a document to the trash bin.
At that point, she can confirm that the trash bin is located in the bottom right corner of
the screen. The task of deleting a document has become learned behavior on the part
of the user. While the visual representation of the trash bin persists, the user’s need
for it to cue memory of how to delete a document has declined—and for many is
completely unnecessary.
31
Chapter 7: Research Agenda The two experiments described in the remaining chapters of this dissertation seek to
understand whether the next evolution in interface design paradigm can be used
effectively by humans on mobile computing machines in task-based situations.
Namely, do visual cues of information and function continue to be required by users in
order to complete tasks using mobile devices? Or can designers move to a paradigm
that uses non-visual conceptual models? Furthermore, if these experiments are
successful in showing that users no longer need to rely on visual cues in ways similar
to the WYSIWYG interactions, can we then describe human-mobile interaction within
a memory framework beyond standard recall and recognition?
The two experiments are based on code that was built for the original Stanford-
based piles project in which participants were asked to store images in “piles” located
outside of the screen (Wang, Hsieh, & Paepcke, 2005). We extended this code and
built two distinct task-based protocols in which participants were asked to work
through multi-step tasks, enacting functions and locating pieces of information that we
described as being located outside of the physical space of the screen. These functions
and pieces of information were not visually represented on the screen. Rather, the
participants were primed to understand that the functions and information existed in
this non-visual form and could be enacted through particular interaction techniques
that referenced the particular, specific space outside of the screen where these items
“lived.”
32
In the two experiments, participants worked through tasks, either in a
WYSIWYG or in a YUMYS paradigm. We took a series of behavioral measurements,
including time on task, total number of interactions between the user and the machine
in order to complete the task, and successful, correct completion of the tasks. The
participants also evaluated the experience. Full descriptions, results, and analyses of
these two experiments follow.
33
Chapter 8: Experiment 1- Introduction As increased computing power can be fashioned into increasingly small devices, there
have arisen several design challenges that are unique to the handheld device as
compared to the mainframe system and personal computers that preceded it. This
project sought to find ways to help alleviate the so-called “small-screen problem.”
Interestingly, the screen is not small because the technology does not allow it to be
bigger; rather the screen is small because we want to be able to fit the device, screen
included, into our pockets.
The primary outcome of the small-screen problem is the lack of “real estate”
on which designers can visually represent the information and functions that a user
needs in order to effectively interact with the handheld machine. The designer cannot
simply make images as small as possible as there is a limit after which human users
cannot effectively see and decipher the visual representation. Therefore other
solutions must come into play.
One path by which a solution may be found is to understand whether it is
necessary that all information and functions be visually represented. This project
imagined an interface paradigm that did not provide visual representation of all
functions that the user needed in order to complete particular tasks. Rather the
paradigm relied in part on a user’s expanded mental model, in which particular
functions “lived” outside of the screen, and the user had to enact these using an
interaction technique that referenced these functions outside of the screen.
34
Chapter 9: Experiment 1- Method
Abstract In order to understand whether users could effectively communicate with a computing
machine using an interface paradigm that did not visually represent all functions
necessary to the completion of a task, we conducted this 2 (device type) X 2 (number
of applications) between-participants study. In it, we examined if participants were
able to complete a multi-step task working within the You Use More than You See
(YUMYS) interface paradigm. We measured participants’ time on task as well as the
participants’ number of interactions with the device in order to complete the required
task. Overall, we found that the participants were able to complete the tasks in the
new interface paradigm. They did so more efficiently on the laptop than on the
handheld device. There were mixed results regarding participants’ subjective ratings.
Overview of Design We conducted a 2 (device: Handheld vs. Laptop) X 2 (number of applications: four
applications vs. eight applications) between-participants study in which participants
completed a multi-step task that required that they enact a variety of web searches,
email, and printing. Participants were required to do a similar multi-step task three
times throughout the session: one time as a practice round, followed by two “test”
rounds. Measures of time on task as well as number of interactions between the
human and the device were taken while the participant completed each round of the
task. Once the participant had completed all three rounds of testing, he was asked to
fill out several measures, including the Positive Affect Negative Affect Scale
35
(PANAS) as well as two series of semantic differentials, one each assessing the
interface and the device on which he worked.
Participants A total of 52 Stanford students participated in this study. They were recruited through
emailed course announcements. All participants were students in undergraduate
classes in the Department of Communication. Participation in the experiment took
about 50 minutes on site. All participants received course credit for their participation.
Materials & Equipment All sessions took place in one of the small “Teaching Assistant” rooms located on
the 3rd floor of Building 120 on the Stanford campus, in the middle of the open Ph.D.
carrels. The devices used included a Samsung device that approximated the feel of a
handheld device and a laptop. The Samsung device is smaller than most standard
tablets and works in a similar way, through inputs received from a hard keyboard, a
soft keyboard, or through stylus input. (The Samsung device approximates the size of
the Apple iPad; this pilot study was conducted before the announcement of the iPad.)
For the purpose of this study, we required the participants to interact with the device
using the stylus. The tasks also required a small bit of typing; participants used the
hard keyboard for this purpose. The laptop worked similarly to other laptop and
desktop personal computing machines. We provided an external mouse and required
that the participants would interact with the laptop by using this external mouse.
When necessary, the participants used the traditional laptop keyboard for typing.
36
Procedure Before running each participant, the research assistant arrived to the study location in
order to set up the room according to the needs of the condition in which the
upcoming participant was assigned. This was necessary for the device independent
variable (handheld vs. laptop). The particular device was situated on a table inside the
study room, along with a chair for the participant to sit in. Additionally, the study
paperwork was put on the table. This included the IRB informed consent form along
with the paper script that would walk the participant through the tasks that he was
expected to do while in session. (See Appendix 1 for research protocol.)
Upon arrival to the testing site, the participant was greeted by the research
assistant and escorted into the testing room. The research assistant confirmed that the
participant was there to be a part of the Interface Study and then proceeded. The
research assistant first provided the informed consent sheet to the participant and
explained that this sheet included some information about the study she were about to
participate in, the lead researcher’s contact information, and the faculty advisor’s
contact information. The research assistant encouraged the participant to take the time
to read over the sheet and then responded to any questions that the participant had
regarding the study. The research assistant told the participant that there was a second
copy of this form that the participant could take with her if she chose to. Once the
participant signed the informed consent form, the researcher moved ahead with the
study.
The research assistant then explained that the participant would be working
through several multi-step tasks on the provided device. Each task consisted of four
37
activities. The participant was first asked to search for information about a specified
movie on the Internet Movie Database (IMDb). Once she had collected that
information, the participant was then asked to find a trailer for the movie on YouTube
and record that URL. The participant was then required to email the information
about the movie along with the URL for the trailer to the study overseers. Finally, she
was asked to print out that information. Each of the three trials followed this same
process, each with a different movie title.
The first trial was a practice trial and was conducted with the researcher in the
room so that the researcher could confirm that the participant was able to complete a
trial if she followed the directions. The second and third trials were completed by the
participant alone. The participant was also asked to read an unrelated article and
complete a Suduko puzzle in between Trials 2 and 3. This was added to distract the
participant from the interaction and thus see whether she was able to complete the
subsequent trial.
Once the participant completed all three trials, she then filled out a series of
measures.
Interaction Type Of particular importance was the fact that all of these four functions—search
the Internet Movie Database, search YouTube, email, and print—were all “located
outside of the screen.” There was no visual representation of these functions on the
device screen itself although a paper map was provided in the test packet. In order to
access these functions, the participant was required to “flick” in the direction of the
38
location where that particular function “lived.” For the handheld conditions, a flick
required that the participant use the stylus, placing the tip of the stylus in the center of
the screen and swiftly but firmly moving the tip of the stylus along the screen toward
the location outside of the screen where the desired function lived. For the laptop
conditions, a flick consisted of a similar action, but required that the participant use
the external mouse, locating the cursor in the middle of the screen, and then sweeping
the mouse such that the cursor would move toward the location where the desired
function lived.
Measures Time on Task: A total number of seconds was captured from the time that each test
trial was launched until that test trial was completed. Thus there is a total number of
seconds that the participant spent completing the practice trial as well as the two test
trials.
Number of Interactions: A total number of interactions was captured while the
participant completed each test trial. An interaction consists of anytime that the
participant tried to enact a flick. For each case, there is a total number of interactions
for the practice trial as well as the two test trials.
Positive Affect Negative Affect Scale (PANAS): After the participant had completed
both tasks, she was asked to assess her own affective state on the two page PANAS
measure, marking her current state of feeling on a five point scale. She was given this
instruction at the beginning of each page: “This scale consists of a number of words
and phrases that describe different feelings and emotions. Read each item and then
39
mark the appropriate answer in the space next to that word. Indicate to what extent
you feel this way right now.” The points on the scale were labeled as follows: 1=Very
slightly or not at all; 2=A little; 3=Moderately; 4=Quite a bit; 5=Extremely.
A series of factor analyses were conducted in order to identify main indices out
of the Positive Affect Negative Affect Scale (PANAS). PANAS data may be reduced
in a number of ways, including assessing an overall positive affect and negative affect.
However, more nuanced factors have been shown. In reviewing these more nuanced
factors, we chose to focus on those indices that made sense in the context of human-
computer interaction. In the positive realm, we selected Attentiveness and Self-
Assurance, the former being a long-time standard measure of media use and the latter
being a more recent focus, particularly in industry, that indicates whether a consumer
will become an invested user of a product over time. On the negative side, we
selected Hostility and Fatigue, the former having been shown to appear as a regular
measure of negative human-computer interaction, particularly as described in Reeves’
and Nass’ Media Equation, and the latter again indicating for industry the extent to
which individuals are willing to continue using a device or interface.
Hostility was comprised of angry, hostile, irritable, scornful, disgusted, and
loathing, Cronbach’s ∝=.90. Self-Assurance was comprised of proud, strong,
confident, bold, daring, and fearless, ∝=.84. Attentiveness was comprised of alert,
attentive, concentrating, and determined, ∝=.77. Fatigue was comprised of sleepy,
tired, sluggish, and drowsy, ∝=.89.
40
Semantic Differentials: After the participant had completed all test trials, she was
asked to assess both the device and the interface by rating it on a page of semantic
differentials, in which pairs of words with opposite meanings were placed on either
end of a five-point scale. The participant received this instruction on the page: “Please
rate the interaction you had with this new DEVICE/INTERFACE using the
following scale. Please consider only how you felt about what you saw on the screen
and your feelings about the interactions with the program.” The participant marked
where on the spectrum between the two words she would rate the device and the
interface.
Four indices resulted from factor analyses conducted on these data: 1) User
Friendly; 2) Engaging; 3) Supportive; and 4) Unique. User Friendly was comprised of
these semantic differential pairs: unapproachable_approachable,
inconvenient_convenient, dull_entertaining, unhelpful_helpful, uninspiring_inspiring,
unsophisticated_intelligent, and not at all useful_useful, ∝=.89 (interface), ∝=.84
(device). Engaging was comprised of these semantic differential pairs:
annoying_pleasing, confusing_easy to understand, unexciting_exciting,
cluttered_clean, and boring_fun, ∝=.70 (interface), ∝=.69 (device). Supportive was
comprised of these semantic differential pairs: indifferent_passionate,
untrustworthy_trustworthy, pessimistic_optimistic, and makes me feel unsafe_makes
me feel safe, ∝=.67 (interface), ∝=.65 (device). Unique was comprised of these
semantic differential pairs: ordinary_unique and unoriginal_creative, ∝=.74
(interface), ∝=.88 (device).
41
Blank Diagram: Lastly, the participant was asked to fill in the labels on a blank
diagram, indicating where each of the functions from the map task “lived” in the
particular interface paradigm. This map was filled out immediately upon finishing the
experiment.
Copies of all of the measures can be found in Appendix 1.
42
Chapter 10: Experiment 1- Results
Behavioral Effects A series of ANOVAs were conducted in order to assess the effects of device
(handheld vs. laptop) and number of applications (four vs. eight) on the behavioral
measures, which included time on task for each of the test trials as well as the total
number of interactions between the human and machine for each of the test trials.
Time on Task: A significant main effect, F(1, 45)=5.71, p<.02, was found for device
on total time on task for Test Trial 2: laptop participants spent less time completing the
task than handheld participants. No effect was found for number of applications.
Figure 1: Laptop participants spent less time completing the tasks in Time Trial 2
than did handheld participants.
43
Number of Interactions: A marginally significant crossover interaction effect, F(1,
45)=2.87, p<.10, was found for number of interactions in Test Trial 1. Laptop
participants with four applications had fewer interactions with the machine than did
laptop participants with eight applications. The opposite was true of handheld
participants.
Figure 2: Laptop participants with four applications had fewer interactions with the
machine than did laptop participants with eight applications. The opposite was true of
handheld participants.
44
A significant main effect, F(1, 45)=10.04, p<.01, was found for device on
number of interactions in Test Trial 2. Laptop participants used fewer interactions to
complete the task than did handheld participants.
Figure 3: Laptop participants used fewer interactions to complete the task than did
handheld participants.
Attitudinal Effects: Positive Affect Negative Scale (PANAS) A series of ANOVAs were conducted in order to assess the effects of device
(handheld vs. laptop) and number of applications (four vs. eight) on each of the
45
attitudinal indices created from the PANAS: Hostility, Self-Assurance, Attentiveness,
and Fatigue.
A marginally significant effect, F(1, 45)=3.06, p<. 09, of device on Hostility
was found, where handheld participants were more hostile than laptop participants.
No effect was found of number of applications on Hostility.
Figure 4: Handheld participants were more hostile than laptop participants.
A marginally significant effect, F(1, 45)=3.27, p<.08, of device on Self-
Assurance was found, where handheld participants were more self-assured than laptop
participants. No effect was found for number of applications on Self-Assurance.
46
Figure 5: Handheld participants were more self-assured than laptop participants.
A main effect, F(1, 45)=8.05, p<.01, of device on Attentiveness was found,
where handheld participants were more attentive than laptop participants. No effect
was found for number of applications on Attentiveness.
47
Figure 6: Handheld participants were more attentive than laptop participants.
A marginally significant effect, F(1, 45)=3.27, p<.08, of number of
applications on Fatigue was found, eight application participants were more fatigued
than four application participants. No effect was found for device on Fatigue.
48
Figure 7: Eight application participants were more fatigued than four application
participants.
Attitudinal Effects: Semantic Differential (Interface) A series of ANOVAs were conducted on the indices created from the semantic
differential (interface): User Friendly, Engaging, Supportive, and Unique. A
marginally significant effect, F(1, 45)=2.89, p<.10, of device on Engaging (Interface)
was found, where laptop participants found the interface more engaging than handheld
participants. There was no effect for number of interactions.
49
Figure 8: Laptop participants found the interface more engaging than handheld
participants.
A marginally significant effect, F(1, 45)=3.84, p<.06, of number of
applications on Supportive (Interface) was found, where four application participants
found the interface more supportive eight application participants. There was no
effect for device.
50
Figure 9: Four application participants found the interface more supportive eight
application participants.
No effects were found on User Friendly and Unique.
Attitudinal Effects: Semantic Differential (Device) A series of ANOVAs were conducted on the indices created from the semantic
differential (device): User Friendly, Engaging, Supportive, and Unique.
A main effect, F(1, 45)=4.80, p<.03, of device on User Friendly (Device) was
found, where handheld participants found the device more supportive than laptop
participants. No effect was found for number of applications.
51
Figure 10: Handheld participants found the device more supportive than laptop
participants.
A main effect, F(1, 45)=8.49, p<.01, of device on Engaging (Device) was
found, where laptop participants found the device more engaging than handheld
participants. No effect was found for number of applications.
52
Figure 11: Laptop participants found the device more engaging than handheld
participants.
A main effect, F(1, 45)=22.41, p<.001, of device on Unique (Device) was
found, where laptop participants found the device more unique than handheld
participants. No effect was found for number of applications.
53
Figure 12: Laptop participants found the device more unique than handheld
participants.
There were no effects for Supportive (Device).
54
Chapter 11: Experiment 1- Discussion In Experiment 1, we asked the question: can participants effectively use a
computing machine where the interface has been designed within the YUMYS design
paradigm? In order to understand this, we created a system in which participants were
required to complete several multi-step tasks. The functions required to complete
these tasks were not visually represented on the screen but rather “lived” outside of the
space of the physical screen. It was incumbent upon the participant to recall that these
functions were there, where each was located, and enact that function in order to
complete the tasks.
Immediately upon completion of data collection, it was clear that individuals
were capable of learning a new interface paradigm that did not depend on the sense of
sight. At the very basic level, all participants were able to complete the tasks assigned
to them, indicating that a movement away from the WYSIWYG paradigm did not
hinder a user’s ability to work with a computing machine, either laptop-sized or
mobile-sized.
In reviewing the behavioral data collected, it is clear that participants were able
to complete the tasks more efficiently using the laptop more so than the handheld
device. While it is useful to understand this, ultimately we are looking for a solution
that can be applied in a mobile setting. It is telling that the tasks were complete-able
in the mobile setting, and while there was a significant difference in the amount of
time and number of interactions used by laptop participants compared to handheld
participants, it is questionable whether this difference is meaningful as well.
55
The significant difference in time was about a minute and a half. Whether
these 90 seconds are truly meaningful depends on the larger context. In the trial in
which these 90 seconds are a significant difference, the participants were required to
complete a multi-step task that included several web searches, sending an email, and
sending a document to print. While 90 seconds added up over a number of such tasks
can be meaningful, we also note that this time difference may be due in part to the
interactions required outside of the true YUMYS interactions. While it was minimal,
there was a small amount of typing required in these tasks, and there was likely greater
ease with typing on the laptop, which used a standard laptop keyboard, over the
handheld, which required the use of the stylus on a soft, on-screen, keyboard.
The entire story is not told through the behavioral data alone. Participants’
assessment of their own affect reveal additional information, indicating that handheld
participants had more extreme reactions, both positive and negative, than did laptop
participants. While handheld participants were more hostile, they were also more
attentive and more self-assured. This may be due in part to the newer nature of the
mobile device. While laptops have been standard fare for most individuals currently
pursuing undergraduate careers, particularly at an institution such as Stanford, the
particular mobile device used was certainly new to all participants as it is a device that
was only commercially available in Korea while these experiments were being
conducted.
56
Nonetheless, the main finding of this experiment, that participants were able to
complete tasks within the YUMYS interface paradigm laid way to the next question: is
YUMYS as good as, or even better than, WYSIWYG for a mobile context?
57
Chapter 12: Experiment 2- Introduction While Experiment 1 demonstrated that users were able to effectively interact with an
interface paradigm in which key functions were not represented visually on the screen,
it did not provide a direct comparison between our YUMYS interface paradigm and
the current primary interface paradigm WYSIWYG (“What You See Is What You
Get”).
The WYSIWYG interface paradigm has been the primary framework in which
designers have built most consumer products. This paradigm is dominated by visual
representation of all functions and information available to users.
Experiment 2 seeks to answer this question: can the YUMYS interface
paradigm provide a user experience that approximates or improves upon the user
experience provided through the WYSIWYG paradigm?
In order to tackle this question, we created tasks on a handheld device that
participants worked through. These tasks were completed either in a YUMYS
interface paradigm or in a WYSIWYG interface paradigm.
For the purpose of this experiment, we tracked the user’s time on task and
number of interactions with the device as representing the efficiency allowed for by
the interface paradigm. We also captured users’ self report of their own perceived
workload, assessments of the device and the interface, and assessment of their own
affect immediately after treatment. Additionally, completed worksheets confirmed
participants’ attention to and completion of the assigned tasks while within the testing
session.
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Chapter 13: Experiment 2 - Method In order to compare the You Use More than You See paradigm against the What You
See Is What You Get Paradigm, we conducted this 2 (interface paradigm, between) X
2 (position, between) X 2 (task type, within) mixed design study. In it, we examined
whether participants could complete standard tasks just as or more effectively in a
YUMYS paradigm as in a WYSIWYG paradigm. We additionally measured
participants’ affective state and subjective ratings of the interface and of the device
immediately post-experiment. Overall we found that participants were more efficient
in the YUMYS paradigm while very few subjective ratings differed between the two
interface states.
Overview of Design We conducted a 2 (interface paradigm: YUMYS vs. WYSIWYG, between) X 2
(position: device on table vs. device held in hand, between) X 2 (task type: content v
map, within) mixed design study in which participants completed two tasks, a content
task and a map task, while in the lab. Measures of time on task as well as number of
interactions between the human and the device were taken while the participant
completed the tasks. Participants were also assessed on completeness and correctness
of tasks. Additionally, participants were asked to fill out a series of measures
throughout the session, including the NASA Task Load Index, the Positive Affect
Negative Affect Scale, and two sets of semantic differentials measuring the
participants’ ratings of the interface and of the device immediately after completing
both tasks. As a measure of memory, participants were also asked to label an interface
59
paradigm map immediately after treatment as well as 24 hours later in an email follow
up survey.
Participants A total of 48 Stanford students participated in this study. They were recruited through
emailed course announcements. All participants were students in a project-based
research course offered through Stanford’s Department of Communication.
Participation in the experiment took between 30 and 60 minutes on site, with a
required five-minute response email the following day. All participants received
course credit for their participation.
Materials & Equipment All sessions took place in one of the small “Teaching Assistant” rooms located on the
3rd floor of Building 120 on the Stanford campus, in the middle of the open Ph.D.
carrels. The same Samsung device was used with each participant. This device is an
early tablet device, smaller than most standard tablets, and works through either
keyboard or stylus input. For the purposes of this study, a stylus input interaction was
used. The device screen was vertically oriented to better approximate many
contemporary popular handheld devices and to better allow for presentation of the two
interface paradigms within the available screen space. For the table condition, the
room was set up with a table and a chair, the device and paper scripts oriented on this
table while the participant worked. For the hand condition, only a chair was available
in the room, and the script was provided to the participant on a clipboard.
60
Procedure Before running each participant, the research assistant arrived to the study location in
order to set up the room according to the needs of the condition in which the
upcoming participant was assigned. This was necessary for the position independent
variable (table vs. hand). For those participants assigned to the table conditions, the
research assistant would set up a work table and one chair in the room and place the
device on the table along with the study’s IRB information sheet as well as the paper
instructions and worksheet for the participant’s first assigned task. (See Appendix 2.1
for the researcher checklist.)
Upon arrival to the testing site, the participant was greeted by the research
assistant and escorted into the testing room and then proceeded. The research assistant
first provided the information sheet to the participant and explained that this sheet
included some information about the study they were able to participate in, the lead
researcher’s contact information, and the faculty advisor’s contact information. The
research assistant encouraged the participant to take the time to read over the sheet and
then responded to any questions that the participant had regarding the study. The
research assistant told the participant that the information sheet was his to take with
him if he wanted to.
The research assistant then explained that the participant would be working on
a couple of tasks throughout the session on the provided device. These tasks would
include a content task—one in which the participant would be reading through a series
of eight web pages, and a map task, in which the participant would be reviewing six
map images.
61
Both tasks provided the participants with information about an event called
“The Relay.” This is an annual run/walk charity event that takes place in early May in
Northern California. The participants were required to fill out paper worksheets that
quizzed them about information they learned about The Relay by working through the
content and map tasks. This event was chosen for three reasons: 1) it allowed for both
content and map tasks; 2) we expected that students would not be familiar with the
event and therefore would not know the answers in advance; and 3) it allowed for a
story that could be accessible to many different interest levels. The participant was
given a paper script that included these worksheets as well as instructions.
The researcher then walked the participant through an example task for the
task type—content or map—that the participant was to complete first. This initial
exercise allowed the research assistant to instruct the participant on how to navigate
the particular task within the specified interface paradigm. The researcher then
handed the stylus to the participant and asked him to “click around for a minute and
make sure it makes sense.” Upon confirming that the participant had the ability to
successfully interact with the device given the particular interface paradigm condition
(which usually took no longer than a minute or two), the researcher reminded her that:
1) she had a worksheet that she needed to fill out; 2) that she should fill out that
worksheet completely and with the correct answers; 3) that she should work quickly
but prioritizing complete, correct answers; and 4) that she should let the research
assistant know when he had completed his packet. The research assistant launched
then launched the test task on the device, returned the device to the participant, and
then left the participant alone in the room to complete the task.
62
Once the participant completed the first task, which included answering all the
questions to the worksheet and filling in the provided measures, the research assistant
returned to the testing room. The research assistant took the paper script from the first
task and traded it for the paper script from the second task.
The same procedure was followed wherein the research assistant launched an
example of the second task and walked through the interaction, showing the
participant how the task would be completed on the device. The stylus and device
were again handed to the participant who was asked to “click around for a minute to
make sure that the interaction made sense.” Once the research assistant confirmed that
the participant was effective in this interaction, the research assistant again reminded
the participant that she had a worksheet that she needed to fill out; that she should look
to fill out that worksheet completely and with the correct answers; that she should
work quickly but prioritizing complete, correct answers; and that she should let the
research assistant know when she had completed her packet. The research assistant
then launched the test task on the device, returned the device to the participant, and
then left the participant alone in the room to complete the task.
Once the participant completed the second task and associated paperwork, the
research assistant retrieved this second packet and the device from the testing room
and provided the participant with her exercise, which was to fill out the Positive Affect
Negative Affect Scale and two semantic differential measures assessing the interface
and the device. She also labeled a blank interface map, indicating where all the
functions for the map task “lived” within the particular interface paradigm. Once this
63
was complete the research assistant thanked the participant and reminded her that she
would be receiving an email from the lead researcher of the study the following day
and that she needed to take a few minutes to respond to that. Then her participation
would be complete.
Task Type The participants each worked through two tasks while in the experiment
session. These were a “content” task and a “map” task. These tasks were chosen as
exemplars of the types of tasks that individuals would be likely to work on using
mobile devices.
The content task required participants to navigate among eight pages of content
and read through the content in order to find answers to questions provided to them on
their paper worksheets. In this task, the participant moved from one page to the next
as indicated by the interface paradigm they were assigned to. Eight buttons were used
in the WYSIWYG condition, one corresponding to each of the eight pages of content.
In the YUMYS condition, participants were told that the eight pages “lived” just
outside the screen, two on each of the four sides of the device. In order to access a
page, the participant had to touch the space on the screen adjacent to where the page
“lived.”
The map task required that the participants review six map images, looking for
pieces of information that would answer the questions asked of them in the paper
script. The participant could manipulate the map image by moving it to the right, left,
up, and down; additionally he could zoom in and out. Lastly he could move to the
64
next map image or to the previous one. In the WYSIWYG condition, these functions
were represented by buttons on the screen. In the YUMYS condition, these functions
again “lived” outside of the screen, and the participant touched the part of the screen
adjacent to the function in order to enact that function. The functions were mapped to
a natural mental model, e.g., the function that controlled being able to see more of the
map to the right “lived” to the right of the screen. (Please see Appendices 2.2 and 2.3
for the researcher and participant scripts.)
Measures Worksheets: The bulk of the manipulation depended upon the participants actually
engaging with the tasks as they were presented in the interface paradigm. To that end,
the participants were asked to fill in the answers to questions on a paper worksheet.
These answers would be found if they completed the tasks as assigned on the device.
(Please see Appendix 2.3 for the worksheets.)
Time on Task: A total number of seconds was captured from the time that each test
task was launched until the participant completed that task. Thus there is a total
number of seconds that the participant spent completing the content task, M=703.30,
SD=218.48 as well as the map task, M=614.74, SD=191.78.
Number of Interactions: A total number of interactions between the human and device
was captured while the participant completed each task. An interaction consisted of
anytime that the participant touched the device’s screen with the stylus. For each case,
there is a total number of interactions for the content task, , M=77.37, SD=56.00, as
well as a total number of interactions for the map task, , M=291.28, SD=158.59.
65
NASA Task Load Index: The participant assessed his current “work load” on the
NASA Task Load Index. He did so 4 times throughout the session: 1) after
completing the content task; 2) after completing the first two of six map mini-tasks; 3)
after completing the second two of six map mini-tasks; and 4) after completing the last
two of six map mini-tasks. This one-page measure allowed the participant to assess
his perceived work load on six scales, including mental demand, physical demand,
temporal demand, performance, effort, and frustration. (Please see Appendix 2.3)
The NASA Task Load Index is expected to reduce to a single factor. After
applying a factor analysis to the NASA Task Load Index data from the four time
points in the study, we consistently found that one component (success) did not load
as strongly as the other components. This makes sense from the standpoint that of the
six scales, success is the only component that asks the participant to assess the
outcome of the work rather than his own state of being during the task.
For the purpose of this study, we analyzed three measures of the NASA Task
Load Index: 1) one factor comprised of all components; 2) one factor comprised of all
components except for success; and 3) the success component alone.
A factor analysis was conducted on all components of the NASA Task Load
Index data from the content task time point to assess whether they could reasonably be
combined into one factor for purposes of analysis. The results indicated that the
Success component did not load properly with the remaining factors. All other
components of the NASA Load Index loaded into one factor, accounting for 60.53%
of the variance, with all components loading between .69 and .88. From these results,
66
two factors were computed: 1) Full NASA Task Load Index, including all the original
components of the NASA Task Load Index, Cronbach’s ∝=.77; 2) and NASA Task
Load without Success, including components except for the Success component,
∝=.80.
A factor analysis was conducted on all of the components of the NASA Task
Load Index for the map task, Time 1, in an effort to confirm whether these data
reacted in the same way that they did for the content task. Again, the results indicated
that the Success component did not load properly with the remaining factors. All
other components of the NASA Task Load Index loaded into one factor, accounting
for 59.97% of the variance, with all components loading between .64 and .81. From
these results, two factors were computed: 1) Full NASA Task Load Index, including
all the original components of the NASA Task Load Index, ∝=.80; 2) and NASA Task
Load without Success, including components except for the success component,
∝=.82.
Factor analyses on the data from the map task, times 2 and 3, resulted
similarly. For time point 2, the results indicated that the success component did not
load properly with the remaining factors. All other components of the NASA Task
Load Index loaded into one factor, accounting for 58.14% of the variance, with all
components loading between .77 and .90. From these results, two factors were
computed: 1) Full NASA Task Load Index, including all the original components of
the NASA Task Load Index, ∝=.84; 2) and NASA Task Load without Success,
including components except for the success component, ∝=.87.
67
For time point 3, the results indicated that the success component did not load
properly with the remaining factors. All other components of the NASA Task Load
Index loaded into one factor, accounting for 56.04% of the variance, with all
components loading between .75 and .87. From these results, two factors were
computed: 1) Full NASA Task Load Index, including all the original components of
the NASA Task Load Index, ∝=.83; 2) and NASA Task Load without Success,
including components except for the success component, ∝=.86.
Semantic Differentials: After the participant had completed all test trials, she was
asked to assess both the device and the interface by rating it on a page of semantic
differentials, in which pairs of words with opposite meanings were placed on either
end of a five-point scale. The participant received this instruction on the page: “Please
rate the interaction you had with this new DEVICE/INTERFACE using the
following scale. Please consider only how you felt about what you saw on the screen
and your feelings about the interactions with the program.” The participant marked
where on the spectrum between the two words she would rate the device and the
interface.
Four indices resulted from factor analyses conducted on these data: 1) User
Friendly; 2) Engaging; 3) Supportive; and 4) Unique. User Friendly was comprised of
these semantic differential pairs: unapproachable_approachable,
inconvenient_convenient, dull_entertaining, unhelpful_helpful, uninspiring_inspiring,
unsophisticated_intelligent, and not at all useful_useful, ∝=.91 (interface), ∝=.86
(device). Engaging was comprised of these semantic differential pairs:
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annoying_pleasing, confusing_easy to understand, unexciting_exciting,
cluttered_clean, and boring_fun, ∝=.73 (interface), ∝=.82 (device). Supportive was
comprised of these semantic differential pairs: indifferent_passionate,
untrustworthy_trustworthy, pessimistic_optimistic, and makes me feel unsafe_makes
me feel safe, ∝=.62 (interface), ∝=.75 (device). Unique was comprised of these
semantic differential pairs: ordinary_unique and unoriginal_creative, ∝=.73
(interface), ∝=.83 (device).
Positive Affect Negative Affect Scale (PANAS): After the participant had completed
both tasks, she was asked to assess her own affective state on the two page PANAS
measure, marking her current state of feeling on a five point scale. She was given this
instruction at the beginning of each page: “This scale consists of a number of words
and phrases that describe different feelings and emotions. Read each item and then
mark the appropriate answer in the space next to that word. Indicate to what extent
you feel this way right now.” The points on the scale were labeled as follows: 1=Very
slightly or not at all; 2=A little; 3=Moderately; 4=Quite a bit; 5=Extremely.
A series of factor analyses were conducted in order to identify main indices out
of the Positive Affect Negative Affect Scale (PANAS). PANAS data may be reduced
in a number of ways, including assessing an overall Positive Affect and an overall
Negative Affect, which we have analyzed here. Additionally, we have selected
several more nuanced factors pertinent to the study of human-mobile interaction.
These are Hostility, Self-Assurance, Attentiveness, and Fatigue.
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Positive Affect was comprised of active, alert, attentive, determined,
enthusiastic, excited, inspired, interested, proud, and strong, ∝=.92. Negative Affect
was comprised of afraid, scared, nervous, jittery, irritable, hostile, guilty, ashamed,
upset, and distressed, ∝=.87. Hostility was comprised of angry, hostile, irritable,
scornful, disgusted, and loathing, ∝=.91. Self-Assurance was comprised of proud,
strong, confident, bold, daring, and fearless, ∝=.88. Attentiveness was comprised of
alert, attentive, concentrating, and determined, ∝=.87. Fatigue was comprised of
sleepy, tired, sluggish, and drowsy, ∝=.75.
Blank Diagram: Lastly, the participant was asked to fill in the labels on a blank
diagram of the interface, indicating where each of the functions from the map task
“lived” in the particular interface paradigm. This diagram was filled out immediately
upon finishing the experiment as well as 24 hours later via email.
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Chapter 14: Experiment 2- Results
Results Overview We analyzed the data from the content task and the map task separately for the
behavioral measures, time on task and number of interactions, as well as the NASA
Task Load Index measures. Conversely, results from the attitudinal measures, the
semantic differential and PANAS factors, were only obtained once at the end of the
study.
Content Task A series of ANOVAs were conducted in order to assess the effects of interface
paradigm (YUMYS vs. WYSIWYG) and position (table vs. hand) on the behavioral
measures, which included time on task and total number of interactions. Additionally,
an ANOVA was run to assess the effects of the independent variables on the three
NASA Task Load factors assessed at the completion of the content task.
A significant main effect, F(1, 44)=3.93, p<.05, was found for position on total
time on task, table participants completing the task more quickly than hand
participants. There was no effect found for interface paradigm.
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Figure 13: Table participants completed the task more quickly than hand participants.
A significant main effect, F(1, 44)=35.59, p<.001, was found for interface
paradigm on number of interactions. The YUMYS participants completed the task
using fewer interactions than the WYSIWYG participants. Additionally, a significant
converging interaction effect, F(1, 44)=10.91, p<.001, was found. For the table,
WYSIWYG participants used more interactions to complete the task than for the table.
No effect was found for position.
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Figure 14: WYSIWYG participants required more interactions to complete the task
than YUMYS participants; this effect was especially pronounced for table participants.
An ANOVA was conducted on the full NASA Task Load Index. A main
effect, F(1, 44)=5.74, p<.02, was found for interface paradigm where YUMYS
participants felt that they worked less hard than WYSIWYG participants. There was
no effect of position.
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Figure 15: YUMYS participants worked less hard than WYSIWYG participants.
An ANOVA was conducted on the NASA Task Load Index without Success.
A main effect, F(1, 44)=7.15, p<.01, was found for interface paradigm where YUMYS
participants felt that they worked less hard than WYSIWYG participants. A
marginally significant converging interaction effect, F(1, 44)=2.69, p<.10, was found
such that for the table position, YUMYS participants felt that they worked
significantly less hard than WYSIWYG participants, while for the hand position, there
was no difference between YUMYS and WYSIWYG participants. There was no main
effect of position.
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Figure 16: YUMYS participants worked less hard than WYSIWYG participants.
This was particularly pronounced for table participants.
An ANOVA was conducted on the success component of the NASA task Load
Index. A main effect, F(1, 44)=3.98, p<.05, was found for interface paradigm where
YUMYS participants perceived their success higher than WYSIWYG participants.
There was no effect of position.
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Figure 17: YUMYS participants felt they were more successful than WYSIWYG
participants.
Map Task A series of ANOVAs were conducted in order to assess the effects of interface
paradigm (YUMYS vs. WYSIWYG) and position (table vs. hand) on the behavioral
measures, which included time on task and total number of interactions. Additionally,
an ANOVA was run to assess the effects of the independent variables on the three
NASA Task Load factors assessed at the completion of each of three mini-map tasks
within the map exercise.
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A significant main effect, F(1, 44)=8.90, p<.01, was found for interface
paradigm on Total Number of Interactions required to complete the map task where
YUMYS participants were able to complete the map task were fewer interactions than
WYSIWYG participants. A marginally significant main effect, F(1, 44)=3.55, p<.07,
for position was found on number of interactions where table participants were able to
complete the map task with fewer interactions than hand participants. No interaction
effect was found.
Figure 18: YUMYS participants required fewer interactions than WYSIWYG
participants. Table participants required fewer interactions than hand participants.
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No significant effects were found for total time on task for the map task.
Time 1: An ANOVA was run on the full NASA Task Load Index and resulted
in a marginally significant effect, F(1, 44)=3.08, p<.09, for interface paradigm, with
YUMYS participants assessing their workload as easier than WYSIWYG participants.
No effect was found for position.
Figure 19: YUMYS participants assessed their workload as lower than WYSIWYG
participants.
An ANOVA was run on the success component and revealed a marginally
significant main effect, F(1, 44)=3.26, p<.08, for position, where table participants
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assessed that they were more successful than hand participants. No effect was found
for interface paradigm.
Figure 20: Table participants perceived that they were more successful than hand
participants. (A lower score indicates a higher perceived success.)
No significant effects were shown at Time 1 for the NASA Task Load Index
without Success.
Time 2: An ANOVA was run on the computed full NASA Task Load Index
and showed a main effect, F(1, 44)=4.34, p<.04, for interface paradigm, with YUMYS
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participants assessing their perceived work load as lower WYSIWYG participants.
There was no effect for position.
Figure 21: YUMYS participants assessed their workload as less than WYSIWYG
participants.
An ANOVA was run on the NASA Task Load Index without Success and
showed a marginally significant main effect, F(1, 44)=3.51, p<.07, for interface
paradigm, with YUMYS participants assessing their workload as less than
WYSIWYG participants. There was no effect for position.
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Figure 22: YUMYS participants assessed their workload as less than WYSIWYG
participants.
No significant effects were shown at Time 2 for the success component.
Time 3: An ANOVA was run on the full NASA Task Load Index and showed
a main effect, F(1, 44)=8.70, p<.01, for interface paradigm, with YUMYS participants
assessing their perceived work load as lower than WYSIWYG participants for Time 3.
Additionally, a marginally significant converging interaction effect, F(1, 44)=3.86,
p<.06, was shown. For the table, WYSIWYG participants assessed their workload
higher than did YUMYS participants.
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Figure 23: YUMYS participants assessed their workload as less than WYSIWYG
participants. The effect is diminished for hand participants.
An ANOVA was run on the NASA Task Load Index without Success and
showed a main effect, F(1, 44)=5.37, p<.03, for interface paradigm, with YUMYS
participants assessing their perceived work load as lower than WYSIWYG
participants. Additionally, a marginally significant converging interaction effect (F(1,
44)=2.81, p<.10) was shown. For the table, WYSIWYG participants perceived their
work load as notably higher than did YUMYS participants. This diminished for the
hand.
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Figure 24: YUMYS participants assessed their workload as less than WYSIWYG
participants. The effect is diminished for hand participants.
An ANOVA was run on the Success component and showed a marginally
significant main effect, F(1, 44)=3.44, p<.07, for interface paradigm, with YUMYS
participants assessing their success as higher than those WYSIWYG participants.
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Figure 25: YUMYS participants assessed their success as higher than WYSIWYG
participants. A lower score indicates a higher perceived success.
Total Across All Time Trials: An ANOVA was run on the full NASA Task
Load Index, combined across all time trials, and showed a main effect, F(1, 44)=5.42,
p<.03, for interface paradigm, with YUMYS participants assessing their perceived
work load as lower than WYSIWYG participants.
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Figure 26: YUMYS participants assessed their workload as less than WYSIWYG
participants.
NASA Task Load Index, across all trials: A repeated measures ANOVA was
run on the computer full NASA Task Load Index with time trial as the repeated
measure. A between-subjects main effect, F(1, 44)=5.42, p<.03, was found where
YUMYS participants assessed their work load as easier than did WYSIWYG
participants. We also saw a significant linear effect, F(1, 44)=19.59, p<.001, for time
trials wherein all participants showed a decrease in perceived work load across time
trials. Lastly, a linear interaction effect, F(1, 44)=8.00, p<.01, was found showing that
YUMYS participants showed a more dramatic drop in perceived work load across
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time trials than did WYSIWYG participants.
Figure 27: YUMYS participants showed a faster rate of decline of perceived work
load than did WYSIWYG participants.
Overall Assessment: Attitudinal Measures After the participants had completed both tasks, they were asked to fill out two
additional measures, assessing the activity as a whole. These attitudinal measures are
reported here.
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Attitudinal Effects: Semantic Differential (Interface) An ANOVA was run on Engaging. A crossover interaction effect, F(1, 44)=4.14,
p<.05, was found. WYSIWYG participants who were also hand participants assessed
the interface as more engaging than YUMYS participants who were also hand
participants.
Figure 28: WYSIWYG participants who were also hand participants assessed the
interface as more engaging than YUMYS participants who were also hand
participants.
An ANOVA was run on Supportive. An marginally significant main effect,
F(1, 44)=3.02, p<.09, was found for position where table participants assessed the
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interface as more supportive than hand participants. There were no effects of interface
paradigm.
Figure 29: Table participants assessed the interface as more supportive than hand
participants.
There were no significant effects on User Friendly or Unique.
Attitudinal Effects: Semantic Differential (Device) An ANOVA was run on Engaging. A significant main effect, F(1, 44)=4.46,
p<.04, was found for Interface Paradigm where YUMYS participants found the device
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more engaging than WYSIWYG participants. A marginally significant main effect,
F(1, 44)=3.60, p<.07, was found for Position where table participants found the device
more engaging hand participants.
Figure 30: YUMYS participants found the device more engaging than WYSIWYG
participants. Table participants found the device more engaging hand participants.
There was no significant effect on User Friendly, Supportive, or Unique.
Attitudinal Effects:PANAS An ANOVA was run on Negative Affect. A main effect, F(1, 44)=4.24, p<.05,
was found for Interface Paradigm, where WYSIWYG participants were more negative
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than YUMYS participants. A main effect, F(1, 44)=3.92, p<.05, was also found for
position, where table participants were more negative than hand participants.
Figure 31: WYSIWYG participants were more negative than YUMYS participants.
Table participants were more negative than hand participants.
An ANOVA was run on Positive Affect. A main effect, F(1, 44)=4.71, p<.04,
was found for Position, where table participants were more positive than hand
participants.
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Figure 32: Table participants were more positive than hand participants.
An ANOVA was run on Hostility. A main effect, F(1, 44)=6.14, p<.02, was
found for Interface Paradigm, where WYSIWYG participants were more hostile than
YUMYS participants. A marginally significant main effect, F(1, 44)=3.67, p<.06, was
found for position, where table participants were more hostile than hand participants.
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Figure 33: WYSIWYG participants were more hostile than YUMYS participants.
Table participants were more hostile than hand participants.
An ANOVA was run on Self-Assurance. A main effect, F(1, 44)=6.00, p<.02,
was found for Interface Paradigm where WYSIWYG participants were more self
assured than YUMYS participants.
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Figure 34: WYSIWYG participants were more self assured than YUMYS
participants.
An ANOVA was run on a transformed Fatigue variable. A marginally
significant main effect, F(1, 44)=3.07, p<.09, was found for Interface Paradigm where
WYSIWYG participants were more fatigued than YUMYS participants.
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Figure 35: WYSIWYG participants were more fatigued than YUMYS participants.
There were no significant effects on Attentiveness.
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Chapter 15: Experiment 2- Discussion In Experiment 2, we asked the question: is the YUMYS interface paradigm as good as,
or even better than, the WYSIWYG interface paradigm for mobile device interface
design? The answer: better.
In order to get to this answer, we developed an experiment in which
participants were required to work through two multi-step tasks—a content task and a
map task. Participants were assigned to complete these tasks either in a system
developed in 1) a WYSIWYG paradigm, in which all functions and access points to
vital content were visually represented on the screen, or 2) in a YUMYS paradigm, in
which all functions and access to vital content “lived” outside the space of the physical
screen. As in Experiment 1, we quickly knew that there was at least parity on one
measure between the two systems in that there was no variation in participants’
abilities to complete the tasks fully and correctly. Completed worksheets were
returned immediately upon experiment completion by each participant, and nearly
every one was 100% complete and correct.
Upon closer examination of the data, it is clear that the YUMYS paradigm was
a significant improvement over WYSIWYG for this mobile interface design project.
YUMYS participants were able to complete the tasks with fewer interactions than the
WYSIWYG participants, and there was no difference in the amount of time taken to
complete the tasks between the two conditions.
It is remarkable that the YUMYS participants were able to complete the tasks
with fewer interactions. Keep in mind that they did not have a visual representation
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available on the screen that they were aiming to touch in order to complete an
interaction that would launch a function. This is remarkable at two levels: the
participant had to recall where on the screen she was to touch; she also had to recall
what function would be launched as a result of that interaction. WYSIWYG
participants were reminded of both of these pieces of information through the
existence of the button visually available to them on the screen.
This finding begins to show support for an evolution in the type of memory
being accessed on the part of the user in order to launch a function. Similar to the
example described in Chapter 6 of the woman asked to show where she would need to
drag a document to delete it, participants in the YUMYS condition may start to
connection a direction and location with particular functions, sparking an enactive
memory process rather than a mere recall process. In this experiment, it was not
necessary that a user actively remember a set of codes such as she would have needed
to if she were working in original command line interfacing. Rather she could begin
to connect the movement or location of the stylus, as extension of her hand, in space to
the resulting function.
The testing of two different types of tasks provide additional support to this
argument of enactive processing. While the map task included intuitive mapping of
come of the functions in the YUMYS condition—the function of moving the map up
lived to the top of the screen, moving the map down lived to the bottom of the
screen—there were a few functions that were not necessarily intuitively mapped in the
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map task. Additionally, there was no intuitive mapping assigned to the content pages
associated with the content task.
Furthermore YUMYS participants assessed their workloads as being easier
than did WYSIWYG participants. YUMYS participants also perceived higher success
in the tasks than did WYSIWYG participants. This bears repeating: YUMYS
participants felt like they were working less and achieving more. This provides
evidence from another route towards the idea that enactive memory is the process by
which YUMYS participants are able to complete tasks in this environment. Returning
to the example of the tennis player described in Chapter 6, we remember that once the
player has learned the strokes, she subsequently accesses them via enactive memory
while in competition. When the ball has been lobbed up into the air from her
opponent, there is no verbal processing needed in which the player remembers the list
of strokes and actively recalls that a smash is the appropriate response in this instance;
there are no verbal or graphic cues represented to her visually so remind her of the
task she is immediately required to do; rather the memory of her body in how to
respond allows her to position herself properly underneath the ball as it falls and enact
an overhand smash to return the ball to her competitor’s side of the net. A similar
process is happening with the YUMYS participants.
A nice additional detail here: YUMYS participants described the device as
being more engaging than did the WYSIWYG participants. Also, self-reported
attitudinal data showed that WYSIWYG participants were more negative, more
hostile, and more fatigued after the completion of the experiment. (They were also
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more self-assured.) Overall, it seems that, in addition to working less and achieving
more, YUMYS participants were simply having more fun.
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Chapter 16: Conclusion This dissertation recommends a paradigm shift in interface design for mobile spaces,
in which we move beyond a reliance on visual representation and begin to explore the
possibility of breaking outside the space of the physical screen. Evidence provided
from two experiments indicates that users can learn a new interface paradigm and
efficiently complete tasks even when all functions are not visually represented. More
so, in direct comparison of a YUMYS instantiation against a Windows instantiation,
we found that YUMYS participants were more efficient, perceived their workload as
easier, their success as higher, and had more fun than did WYSIWYG participants.
This opens the door for designers to innovate beyond the confines of the
physical screen and may eliminate the “small screen” problem identified in so much
literature. Once we no longer hold ourselves to figuring out how to make room for
visual representations, by space sharing or time shifting or other mechanisms, and
understand that we can rely on the user’s ability to expand a mental model past the
constraints of the visual, then designers can build on the YUMYS concept described in
this dissertation.
There is a wide swath of work that could follow these initial experiments,
including focusing on repeated use over time, developing for a variety of mobile
device platforms, understanding which input mechanisms are best suited for the
YUMYS paradigm, and testing out more task types.
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Appendix 1.1—Experiment 1 Protocol Step 1
Thank you for participating in this study about computing and task interaction. Over the course of the next 45 minutes, you will work through a series of tasks, both on and off the computer, and will answer some questions about your interactions. Your participation is completely voluntary—you may leave at anytime.
Before you begin, please take a look at the next two forms. One is a consent form. Please read it carefully so that you understand your participation in this activity and then sign it. The second form is a questionnaire. Please fill that out as well.
When you are done with these, please hand them to the researcher.
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IRB protocol 14673 Page 1 of 2
CONSENT FORM
FOR QUESTIONS ABOUT THE STUDY, CONTACT:
Katherine J. Murray, Stanford University, Building 120, Room 300, 415-513-6420.
DESCRIPTION: You are invited to participate in a research study on computing interfaces for traditional and handheld Windows-based PC machines. You will be asked to work through a series of tasks using a new interface paradigm. You will be asked to fill out several questionnaires along the way asking you to evaluate your current mood as well as your assessment of the interface you will be using. Your interactions with the computer will be recorded.
All data, including both your written responses as well as your interactions with the device, will be stored separately from any identifying information. These data will be stored in digital format on computers accessible only to the members of the project team.
RISKS AND BENEFITS: The foreseeable risk for participants is that they may feel some frustration from working through the tasks using an unfamiliar interface paradigm and an unfamiliar Windows-based PC machine. The benefit which may reasonably be expected to result from this study is that you will contribute to design of future interface paradigms that may be increasingly necessary as screen sizes continue to shift over time. We cannot and do not guarantee or promise that you will receive any benefits from this study. Your decision whether or not to participate in this study will not affect your employment/medical care/grades in school.
TIME INVOLVEMENT: Your participation in this experiment will take approximately one hour.
COMPENSATION: You will receive an hour of credit for participation in this study OR $15 cash. You are only eligible to receive cash if you are a U.S. citizen or otherwise eligible to receive payment for work. You are required to provide us with a social security number in order to receive financial compensation.
SUBJECT'S RIGHTS: If you have read this form and have decided to participate in this project, please understand your participation is voluntary and you have the right to withdraw your consent or discontinue participation at any time without penalty or loss of benefits to which you are otherwise entitled. You have the right to refuse to answer particular questions. Your individual privacy will be maintained in all published and written data resulting from the study.
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CONTACT INFORMATION:
Questions, Concerns, or Complaints: If you have any questions, concerns or complaints about this research study, its procedures, risks and benefits, or alternative courses of treatment, you should ask the Protocol Director, Katherine J. Murray. You may contact her now or later at 415-513-6420.
Emergency Contact: If you feel you have been hurt by being a part of this study, or need immediate assistance please contact Vaden Health Center at 650-498-2338 or the Faculty Sponsor, Professor Clifford Nass, at 650-723-5499.
Independent of the Research Team Contact: If you are not satisfied with the manner in which this study is being conducted, or if you have any concerns, complaints, or general questions about the research or your rights as a research study subject, please contact the Stanford Institutional Review Board (IRB) to speak to an informed individual who is independent of the research team at (650)- 723-5244 or toll free at 1-866- 680-2906. Or write the Stanford IRB, Administrative Panels Office, Stanford University, Stanford, CA 94305-5401. In addition, please call the Stanford IRB at (650)- 723-5244 or toll free at 1-866-680-2906 if you wish to speak to someone other than the research team or if you cannot reach the research team.
The second consent form is also yours to take with you.
SIGNATURE _____________________________ DATE ____________
Address__________________________________________
City____________________ State _______ ZIP _________
Protocol Approval Date: 5/22/2008
Protocol Expiration Date: 4/30/2009
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Survey This scale consists of a number of words and phrases that describe different feelings and emotions. Read each item and then mark the appropriate answer in the space next to that word. Indicate t o what extent you have felt this way right now.
Very slightly or not at all
A little Moderately Quite a Bit Extremely
Cheerful 1 2 3 4 5 Sad 1 2 3 4 5
Active 1 2 3 4 5 Angry at Self 1 2 3 4 5
Disgusted 1 2 3 4 5 Calm 1 2 3 4 5 Guilty 1 2 3 4 5
Enthusiastic 1 2 3 4 5 Attentive 1 2 3 4 5
Afraid 1 2 3 4 5 Joyful 1 2 3 4 5
Downhearted 1 2 3 4 5 Bashful 1 2 3 4 5 Tired 1 2 3 4 5
Nervous 1 2 3 4 5 Sheepish 1 2 3 4 5 Sluggish 1 2 3 4 5 Amazed 1 2 3 4 5 Lonely 1 2 3 4 5
Distressed 1 2 3 4 5 Daring 1 2 3 4 5 Shaky 1 2 3 4 5 Sleepy 1 2 3 4 5
Blameworthy 1 2 3 4 5 Surprised 1 2 3 4 5
Happy 1 2 3 4 5 Excited 1 2 3 4 5
Determined 1 2 3 4 5 Strong 1 2 3 4 5 Timid 1 2 3 4 5 Hostile 1 2 3 4 5
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This scale consists of a number of words and phrases that describe different feelings and emotions. Read each item and then mark the appropriate answer in the space next to that word. Indicate t o what extent you have felt this way right now.
Very slightly or not at all
A little Moderately Quite a Bit Extremely
Frightened 1 2 3 4 5 Scornful 1 2 3 4 5
Alone 1 2 3 4 5 Proud 1 2 3 4 5
Astonished 1 2 3 4 5 Relaxed 1 2 3 4 5
Alert 1 2 3 4 5 Jittery 1 2 3 4 5
Interested 1 2 3 4 5 Irritable 1 2 3 4 5 Upset 1 2 3 4 5 Lively 1 2 3 4 5
Loathing 1 2 3 4 5 Delighted 1 2 3 4 5
Angry 1 2 3 4 5 Ashamed 1 2 3 4 5 Confident 1 2 3 4 5 Inspired 1 2 3 4 5
Bold 1 2 3 4 5 At Ease 1 2 3 4 5
Energetic 1 2 3 4 5 Fearless 1 2 3 4 5
Blue 1 2 3 4 5 Scared 1 2 3 4 5
Concentrating 1 2 3 4 5 Disgusted with Self
1 2 3 4 5
Shy 1 2 3 4 5 Drowsy 1 2 3 4 5
Dissatisfied with Self
1 2 3 4 5
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Step 2
Throughout this activity, you will be using a Windows-based PC to complete a series of tasks. You will be performing these tasks with a new interface that may be unfamiliar to you. To get started, we’d like you to walk through a task using this new interface so that you can become comfortable with the interaction.
Please read the following overview and then follow the instructions to learn the new interface.
The interface uses space outside of actual computer screen to locate applications, such as email, print, or any Web-enabled activities, such as Facebook or Wikipedia. Rather than opening these applications by clicking on an icon or going to your start menu and selecting the application, as you might do with a traditional Windows interface, you access them by dragging an object towards the application you want to use.
For example, in order to send an email, you simply need to write the email in a text editor, save that document to the desktop, and then drag the document towards the side of the screen where your email application is located.
These actions can also be performed on a couple of words within a document. For instance, you may want to search for a clip on YouTube about the Stanford baseball team. In order to do this, you would simply type “Stanford baseball team” into the text editor, select those words, and then drag them towards the side of the screen where the YouTube application is located.
This may sound confusing, so let’s try performing a multi-step task using this interface. You are going to find information about a movie before printing and emailing this information to us. Follow each step as written.
1) Double click the icon marked “Trial 0.” This icon is found on your desktop. 2) You will see a series of labels on the edges of your screen. These are the locations of your applications. Using this new interface, you can drag objects to the screen-edge labels to perform actions on them. We’ll show you how this is done below. 3) In the middle of the screen you will see a text editor. Type the name of the movie you want to search for — in this case, let’s search for “Transformers.” 4) Now highlight the word you just typed by moving your mouse and dragging across the length of the word. 5) You can then take this text selection and flick it to one of the labels by dragging. Flick it to IMDB now. 6) A web browser should launch, automatically searching IMDB for the word “Transformers.” 7) Find the release date, screenplay writer, and actor who played “Defense Secretary John Keller.” Switch back to the Text Editor application — it should
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be minimized in the bottom of your screen — and type in the three pieces of information underneath “Transformers,” one per line. 8) Now select “Transformers” again and flick it to the YouTube label. As before, it should launch a web browser and should search for “Transformers” on YouTube. 9) Copy and paste the YouTube URL into the text editor (again, the latter should be minimized in the bottom of your Start Bar). 10) Now save this document on your desktop and close the Text Editor. 11) Drag the document itself to the label marked “E-mail.” This will launch Gmail and will open an account. 12) From the account that is already opened, send this document to [email protected] . Enter as the subject “Step 2.” 13) Close the E-mail application. 14) Drag the document to the “Print” label. 15) Print the document.
When you are finished with this part of the study, please hand the consent form, survey, print out, and the pages you have read so far to the researcher.
Once you have handed off the pages, please turn the page and move on to the Step 3.
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Step 3
Following the same procedure outlined in the previous step, complete the task below. This time, double click “Trial 1.”
Use the computer to search IMDB for the following movie:
Howard the Duck
and find the following information about the film:
a) release year b) voice actor of the character “Howard the Duck” c) name of the director
Then search YouTube with the query “Howard the Duck” to find the URL of the first video clip you see.
Then use the computer to write an email to
with all of the above information on individual lines.
Then print the document.
Once you have completed this task, please turn the page and move on to Step 4.
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Step 4
Please read this article.
Nation Agrees Not To Talk About Politics
April 18, 2008 | Issue 44•16
WASHINGTON—After months of fevered and contentious political discourse, the U.S. populace unanimously agreed Monday that, before somebody gets upset and things get out of hand, it would be better to just stop talking about politics altogether.
Designed to reverse the trend of heated discussions on topics ranging from the Democrats' shifting stance on NAFTA to Sen. John McCain's support for the Iraq War, the nationwide change in subject is effective immediately.
The White House will not even be mentioned for at least six months.
"There's no point getting the country all riled up talking about politics, especially right before a big election like this," 43-year-old Pittsburgh resident Eric Daniels said. "With terrorism and the economy and all these other problems on our minds, nobody wants to talk about which candidate can best restore faith in America both at home and abroad."
"Baseball season just started," Daniels added. "How about them Pirates?"
The decision by all 301,139,947 U.S. citizens to talk about something else is expected to last the more than six months leading up to the presidential election on Nov. 4. During that time, the nation has agreed to supplant all lively debates and impassioned arguments about politics with topics such as movies, music, summertime, and, in some rare cases, personal matters like family, relationships, and feelings.
Anything, Americans strongly reiterated, so long as it is not politics.
A Zogby International poll conducted last week reflected the country's distaste for political debate. When asked if they preferred the Republican emphasis on national security or the more Democratic commitment to domestic issues, 73 percent of respondents agreed to disagree on the matter and just leave it at that; 16 percent called the topic of Obama versus Clinton "touchy" and not worth talking about if it could offend someone; and 11 percent said that for the sake of everyone having a good, hassle-free year, it is probably best to just let it go and not worry about who the 44th president will be.
In addition, nine out of 10 Americans polled stressed that with the dollar's poor performance and record-high gas prices, this is neither the time nor the place to be talking about politics in the first place.
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"If people need to talk about Hillary Clinton's health care proposal, I hope they have the decency to let me know so I can go somewhere else first," Jacksonville, FL resident Katherine Watson, 37, said. "Or at least make the conversations more interesting. Maybe talk about Barack Obama's smile or John McCain's weird shoulder thing."
Citizens have also reportedly experienced much less tension in the nation since the ban was instated. Moreover, millions have expressed relief and enthusiasm that, given the backgrounds of the candidates in this election, the injunction has led to a drop in awkward discussions of race, gender, and age.
"Yesterday I had a wonderful, hour-long conversation about how crazy [contestant] Andrew [D'Ambrosi] on Top Chef is, but at least he adds an interesting dynamic to the show," Deirdre Miles, 26, of Sacramento said. "It was such a relief to know that nobody would be bringing up superdelegates, the Pennsylvania primary, or John McCain's comment about having our troops in Iraq for the next 100 years. I've got two brothers fighting over there, so that is the last thing I want to think about right now."
Even as the country braces for a potential recession, a number of media outlets claim that the injunction on talking politics could be a boon to business. With television, newspapers, and radio stations all forced to cover only sports and entertainment, ad revenue and ratings are expected to soar in every major market nationwide.
For their part, politicians have largely been supportive of the move.
"The president is proud that the American people have come together on such an important issue," White House press secretary Dana Perino told reporters at a briefing Tuesday. "He supports their decision wholeheartedly, and thinks U.S. citizens should focus on relaxing and having a good time in the upcoming months."
Added Perino, "We'll take care of the politics for you."
Though the moratorium will likely be lifted after the election, the 1984 agreement between Americans to avoid discussing religion has been extended until 2024.
When you are finished, please turn the page and move on to Step 5.
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Step 5
Then complete the sudoku puzzle following the article. The objective of sudoku is to fill a 9x9 grid so that each column, row, and each of the nine internal 3x3 boxes contains every number from 1 to 9 only once. Here’s an example puzzle and solution.
When you are finished, please turn the page and move on to Step 6.
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Step 6
Follow the same procedure outlined in the tutorial to complete the task below. This time, double click “Trial 2.” If you would like to see the image that shows you where the applications are located, please click on the button in the bottom right hand corner labeled “See Image.”
Use the computer to search IMDB for the following movie:
Sixteen Candles
and find the following information about the film:
a) release year b) actor who played the character “Jim Baker” c) name of the director
Then search YouTube with the query “Sixteen Candles” to find the URL of the first video clip you see.
Then use the computer to write an email to
with all of the above information on individual lines.
Then print the document.
When you are finished, please turn the page and move on to Step 7.
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Step 7
Thank you for completing this study. Please respond to the questionnaires on the final few pages of this packet and return them along with the printouts and this instruction packet to your researcher.
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Please rate the interaction you had with this new interface using the following scale. Please consider only how you feel about what you saw on the screen and your feelings about the interactions with the program.
Not at all useful 1 2 3 4 5 Useful Annoying 1 2 3 4 5 Pleasing Confusing 1 2 3 4 5 Easy to understand Unexciting 1 2 3 4 5 Exciting Cluttered 1 2 3 4 5 Clean Boring 1 2 3 4 5 Fun
Unfriendly 1 2 3 4 5 Friendly Unoriginal 1 2 3 4 5 Creative
Makes me feel unsafe 1 2 3 4 5 Makes me feel safe Unapproachable 1 2 3 4 5 Approachable
Forgettable 1 2 3 4 5 Captivating Inconvenient 1 2 3 4 5 Convenient
Dull 1 2 3 4 5 Entertaining Unhelpful 1 2 3 4 5 Helpful
Uninspiring 1 2 3 4 5 Inspiring Unsophisticated 1 2 3 4 5 Intelligent
Pessimistic 1 2 3 4 5 Optimistic Indifferent 1 2 3 4 5 Passionate
Untrustworthy 1 2 3 4 5 Trustworthy Ordinary 1 2 3 4 5 Unique
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Please rate the DEVICE you used on the following scale. Please rate the computer itself aside from the interactions with the interface.
Not at all useful 1 2 3 4 5 Useful Annoying 1 2 3 4 5 Pleasing Confusing 1 2 3 4 5 Easy to understand Unexciting 1 2 3 4 5 Exciting Cluttered 1 2 3 4 5 Clean Boring 1 2 3 4 5 Fun
Unfriendly 1 2 3 4 5 Friendly Unoriginal 1 2 3 4 5 Creative
Makes me feel unsafe 1 2 3 4 5 Makes me feel safe Unapproachable 1 2 3 4 5 Approachable
Forgettable 1 2 3 4 5 Captivating Inconvenient 1 2 3 4 5 Convenient
Dull 1 2 3 4 5 Entertaining Unhelpful 1 2 3 4 5 Helpful
Uninspiring 1 2 3 4 5 Inspiring Unsophisticated 1 2 3 4 5 Intelligent
Pessimistic 1 2 3 4 5 Optimistic Indifferent 1 2 3 4 5 Passionate
Untrustworthy 1 2 3 4 5 Trustworthy Ordinary 1 2 3 4 5 Unique
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Survey This scale consists of a number of words and phrases that describe different feelings and emotions. Read each item and then mark the appropriate answer in the space next to that word. Indicate t o what extent you have felt this way right now.
Very slightly or not at all
A little Moderately Quite a Bit Extremely
Cheerful 1 2 3 4 5 Sad 1 2 3 4 5
Active 1 2 3 4 5 Angry at Self 1 2 3 4 5
Disgusted 1 2 3 4 5 Calm 1 2 3 4 5 Guilty 1 2 3 4 5
Enthusiastic 1 2 3 4 5 Attentive 1 2 3 4 5
Afraid 1 2 3 4 5 Joyful 1 2 3 4 5
Downhearted 1 2 3 4 5 Bashful 1 2 3 4 5 Tired 1 2 3 4 5
Nervous 1 2 3 4 5 Sheepish 1 2 3 4 5 Sluggish 1 2 3 4 5 Amazed 1 2 3 4 5 Lonely 1 2 3 4 5
Distressed 1 2 3 4 5 Daring 1 2 3 4 5 Shaky 1 2 3 4 5 Sleepy 1 2 3 4 5
Blameworthy 1 2 3 4 5 Surprised 1 2 3 4 5
Happy 1 2 3 4 5 Excited 1 2 3 4 5
Determined 1 2 3 4 5 Strong 1 2 3 4 5 Timid 1 2 3 4 5 Hostile 1 2 3 4 5
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This scale consists of a number of words and phrases that describe different feelings and emotions. Read each item and then mark the appropriate answer in the space next to that word. Indicate t o what extent you have felt this way right now.
Very slightly or not at all
A little Moderately Quite a Bit Extremely
Frightened 1 2 3 4 5 Scornful 1 2 3 4 5
Alone 1 2 3 4 5 Proud 1 2 3 4 5
Astonished 1 2 3 4 5 Relaxed 1 2 3 4 5
Alert 1 2 3 4 5 Jittery 1 2 3 4 5
Interested 1 2 3 4 5 Irritable 1 2 3 4 5 Upset 1 2 3 4 5 Lively 1 2 3 4 5
Loathing 1 2 3 4 5 Delighted 1 2 3 4 5
Angry 1 2 3 4 5 Ashamed 1 2 3 4 5 Confident 1 2 3 4 5 Inspired 1 2 3 4 5
Bold 1 2 3 4 5 At Ease 1 2 3 4 5
Energetic 1 2 3 4 5 Fearless 1 2 3 4 5
Blue 1 2 3 4 5 Scared 1 2 3 4 5
Concentrating 1 2 3 4 5 Disgusted with Self
1 2 3 4 5
Shy 1 2 3 4 5 Drowsy 1 2 3 4 5
Dissatisfied with Self
1 2 3 4 5
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Appendix 1.2—Correlations, Dependent Variables Correlations: # of Flicks
Correlations t0 # of flicks t1 # of flicks t2 # of flicks
Pearson Correlation
1 .118 .064
Sig. (2-tailed) .405 .652
t0 # of flicks
N 52 52 52 Pearson Correlation
.118 1 .030
Sig. (2-tailed) .405 .831
t1 # of flicks
N 52 52 52 Pearson Correlation
.064 .030 1
Sig. (2-tailed) .652 .831
t2 # of flicks
N 52 52 52
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Correlations: Total Duration
Correlations
t0 Total Duration
t1 Total Duration
t2 Total Duration
Pearson Correlation
1 .076 .241
Sig. (2-tailed) .592 .085
t0 Total Duration
N 52 52 52 Pearson Correlation
.076 1 .170
Sig. (2-tailed) .592 .228
t1 Total Duration
N 52 52 52 Pearson Correlation
.241 .170 1
Sig. (2-tailed) .085 .228
t2 Total Duration
N 52 52 52
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Correlations: PANAS
Correlations
Fatigue Hostility
SelfAssurance
Attentive
Pearson Correlation
1 -.115 -.037 -.112
Sig. (2-tailed) .378 .778 .395
Fatigue
N 60 60 60 60
Pearson Correlation
-.115 1 .012 .251
Sig. (2-tailed) .378 .927 .053
Hostility
N 60 60 60 60
Pearson Correlation
-.037 .012 1 .587**
Sig. (2-tailed) .778 .927 .000
SelfAssurance
N 60 60 60 60
Pearson Correlation
-.112 .251 .587** 1
Sig. (2-tailed) .395 .053 .000
Attentive
N 60 60 60 60
**. Correlation is significant at the 0.01 level (2-tailed).
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Correlations: Semantic Differential (Device)
Correlations
UserFriendly_D
Engaging_D
Supportive_D
Unique_D
Pearson Correlation
1 .728** .715** .336*
Sig. (2-tailed) .000 .000 .011
UserFriendly_D
N 56 56 56 56
Pearson Correlation
.728** 1 .575** .424**
Sig. (2-tailed) .000 .000 .001
Engaging_D
N 56 56 56 56
Pearson Correlation
.715** .575** 1 .214
Sig. (2-tailed) .000 .000 .097
Supportive_D
N 56 56 56 56
Pearson Correlation
.336* .424** .214 1
Sig. (2-tailed) .011 .001 .097
Unique_D
N 56 56 56 56
**. Correlation is significant at the 0.01 level (2-tailed).
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Correlations
UserFriendly_D
Engaging_D
Supportive_D
Unique_D
Pearson Correlation
1 .728** .715** .336*
Sig. (2-tailed) .000 .000 .011
UserFriendly_D
N 56 56 56 56
Pearson Correlation
.728** 1 .575** .424**
Sig. (2-tailed) .000 .000 .001
Engaging_D
N 56 56 56 56
Pearson Correlation
.715** .575** 1 .214
Sig. (2-tailed) .000 .000 .097
Supportive_D
N 56 56 56 56
Pearson Correlation
.336* .424** .214 1
Sig. (2-tailed) .011 .001 .097
Unique_D
N 56 56 56 56
**. Correlation is significant at the 0.01 level (2-tailed).
*. Correlation is significant at the 0.05 level (2-tailed).
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Correlations: Semantic Differential (Interface)
Correlations
UserFriendly_I
Engaging_I
Supportive_I
Unique_I
Pearson Correlation
1 .765** .739** .432**
Sig. (2-tailed) .000 .000 .001
UserFriendly_I
N 60 60 60 60
Pearson Correlation
.765** 1 .610** .472**
Sig. (2-tailed) .000 .000 .000
Engaging_I
N 60 60 60 60
Pearson Correlation
.739** .610** 1 .572**
Sig. (2-tailed) .000 .000 .000
Supportive_I
N 60 60 60 60
Pearson Correlation
.432** .472** .572** 1
Sig. (2-tailed) .001 .000 .000
Unique_I
N 60 60 60 60
**. Correlation is significant at the 0.01 level (2-tailed).
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Appendix 2.1— Experiment 2 Researcher Checklist RESEARCHER CHECKLIST
Before the participant arrives… 1. Researcher arrives to testing site. 2. Researcher checks that equipment and room are in working order. 3. Researcher checks participant spreadsheet to identify which condition the
upcoming participant will be working in. 4. Researcher sets up device in testing room according to which condition the
upcoming participant will be working in. 5. Researcher puts together a questionnaire packet for the participant. (NB:
Please email Kat if these sheets are running low so that more copies can be made.)
6. Wait for participant to arrive. YUMYS Interface
WYSIWYG Interface
Device on Table CONDITION 1
CONDITION 2
Device in Hand CONDITION 3
CONDITION 4
Condition 1 Room & Device Set Up If participant is in Condition 1, then set up the device on the table such that the device is leaning up as if it’s on an easel. Remove stylus and place it in front of the device on the table. Launch the YUMYS data entry task. Check that the device and program are working properly by entering in the first few numbers. Condition 2 Room & Device Set Up If participant is in Condition 2, then set up the device on the table such that the device is leaning up as if it’s on an easel. Remove stylus and place it in front of the device on the table. Launch the WYSIWYG data entry task. Check that the device and program are working properly by entering in the first few numbers. Condition 3 Room & Device Set Up If participant is in Condition 3, then move the table out of the testing room. Set up the device and place it in a chair. Remove stylus and place it in front of the device on the chair. Launch the YUMYS data entry task. Check that the device and program are working properly by working entering in the first few numbers. You will instruct the participant to hold the device in his hand while he completes the tasks. Condition 4 Room & Device Set Up
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If participant is in Condition 4, then move the table out of the testing room. Set up the device and place it in a chair. Remove stylus and place it in front of the device on the chair. Launch the WYSIWYG data entry task. Check that the device and program are working properly by working entering in the first few numbers. You will instruct the participant to hold the device in his hand while he completes the tasks. Once the participant arrives…
7. Welcome participant. 8. Show participant into testing room. 9. Give participant copy of the information sheet. 10. Follow script.
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Appendix 2.2— Experiment 2 Script (YUMYS Condition)
Introduction “Thanks for joining us today. This may look familiar to you as the CHIMe Lab has been running a couple of years’ worth of experiments with this device. This may be similar to something you’ve done in the past, and that’s OK. It’s also fine if you’ve never done this before.
“Over the course of about the next hour, you’ll work through some tasks on this device. This device is a little finicky—it is probably older than your cell phone, so you’ll want to be a little patient as you work through the tasks.
“This paper script will walk you through what you’re supposed to do with the device. It also includes a worksheet to fill out, which has questions related to the content you’ll read or images you’ll see while working through the outlined tasks. You’ll want to find the right answer to each question—there is a correct answer to each question, and it can be if you complete the assigned tasks. You’ll also fill out a few short questionnaires along the way.
“Let’s walk through one example together.” Content Task Instruction YUMYS
<researcher to launch the example by doubleclicking on the short cut for the content example; this can be found: on Desktop folder called “Kat’s Project” doubleclick to open this folder doubleclick on DEMO – YUMYS - TEXT researcher should adjust window to top of screen so that it is flush with the top of the screen; then hand pencil, which we are using as the stylus, to the participant so that s/he can work through the tasks>
“We’ll walk though this example together, and then you’ll do one on your own. Again, keep in mind that this device can sometimes run kind of slowly.
“So now you see something that looks sort of like a web page—there’s some content here that you can read through. There are 8 pages of content altogether, and you are welcome to navigate through these pages of content in any order. Now you don’t see any buttons to click on to get to the pages. Rather these pages of content live outside
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of your screen—two on each side. Two at the top, two at the bottom, and two on either the right or left side. “You navigate to these pages, by touching the space on the screen adjacent to where that page “lives.” So for instance, if you wanted to launch the page that lives on the top half of the right side of the screen, you’d simply touch the screen on the right side and in the upper half. “You would continue to do this for all 8 pages. Why don’t give it a try and click around for a bit to a few different pages to make sure it makes sense? Just make sure you’re clicking inside the boundaries of the content screen itself.”
<researcher should encourage participant to do this a few times and make sure that the user is able to enact the interaction easily>
“Do you have any questions?”
<researcher answers questions as needed>
“OK, let me get this started for you. By the way, you may encounter an error message that comes up in another language. Just click “OK” to send the error message away. You don’t need to pay any attention to it.”
<researcher to double click on short cut for the “Content Task.” on Desktop folder called “Kat’s Project” doubleclick to open this folder doubleclick on YUMYS – TEXT researcher to make sure that the software launches properly; researcher should adjust window to top of screen so that it is flush with the top of the screen.> “OK, I’ll leave you with the script. When you’re completely done with your task, just click on that Done button on the bottom of the screen. Then come get me, and we’ll take a look at the worksheet.”
<researcher leaves script of Content task and leaves room, sitting within eyesight of the participant>
……
<participant finishes, lets researcher know>
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Map Task Instruction YUMYS “OK, great.”
<researcher looks to make sure that the worksheet is complete; if it isn’t, ask why and encourage the participant to get all the answers in the next round>
“Now you are going to do a set of tasks involving looking at and reading some maps. You’ll have a worksheet of answers to fill out, and you’ll want to find the right answer to each question—there is a correct answer to each question, and it can be found if you complete the assigned tasks.
“Let’s walk through one example together.”
<researcher to launch the example by doubleclicking on the short cut for the Map Example: on Desktop folder called “Kat’s Project” doubleclick to open this folder doubleclick on DEMO – YUMYS - MAP researcher should adjust window to top of screen so that it is flush with the top of the screen; then hand pencil to the participant so that s/he can work through the tasks>
“We’ll walk though this example together, and then you’ll do one on your own. Again, keep in mind that this device can sometimes run kind of slowly.
“What you see here is an image of a map. You can manipulate the map using several different functions, including doing things like zooming in and out. However, you’ll notice that there are no buttons for these functions. Rather these functions live outside of the screen. In order to enact these functions, you simply have to touch the screen adjacent to the space where the particular function lives. Let’s talk all those functions through. “In order to move the map left or right, up or down, you simply need to click on the left edge of the screen, right edge of the screen, or top or bottom. Clicking on the right edge of the screen moves the map to the right, and so forth. Just making sure you’re clicking inside the boundaries of the image itself.” <researcher instructs participant to click around, make sure it works and makes sense>
“Also you can zoom in and out. These functions live just outside the screen in the upper corners. You zoom in by clicking on the upper right hand corner. You zoom
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out by clicking in the upper left hand corner. Just make sure you’re clicking inside the image in the corners.”
<researcher instructs participant to click around, make sure it works and makes sense>
“Lastly, you can move to the next image, or back to the previous image. There are 6 images in all for you to look through. The ‘next’ and ‘previous’ functions live outside the bottom corners of the screen. You’ll click on the bottom right hand corner to go to the next map and the bottom left hand corner to go to the previous map.”
<researcher should encourage participant to do this a few times and make sure that the user is able to enact the interaction easily>
“Do you have any questions?”
<researcher answers questions as needed>
“OK, let me get this started for you. By the way, you may encounter an error message that comes up in another language. Just click “OK” to send the error message away. You don’t need to pay any attention to it.” <researcher to double click on short cut for the “Map Task.” on Desktop folder called “Kat’s Project” doubleclick to open this folder doubleclick on YUMYS - MAP researcher to make sure that the software launches properly; researcher should adjust window to top of screen so that it is flush with the top of the screen.>
“OK, I’ll leave you with the script. When you’re completely done with your task, go ahead and close out of the task by clicking on the Done button at the bottom of the screen. Then come get me, and we’ll take a look at the worksheet.”
<researcher leaves script of Map task and leaves room, sitting within eyesight of the participant> ……
<participant finishes, lets researcher know>
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Once Participant is Done with Both Tasks “OK, great.”
<researcher looks to make sure that the worksheet is complete; if it isn’t, ask why> “Now I just need you to fill a few more items.” <researcher gives participant final packet of questionnaires; this includes the two semantic differentials, the PANAS, and the blank map.>
“Excellent. You’ll be receiving an email tomorrow morning from Kat Murray asking just a few follow up questions. This email is also a part of the study. Be sure to respond to her so that you’ll get credit for your participation. Thanks again!”
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Appendix 2.3— Experiment 2 Participant Documents IRB protocol 18592 Page 1 of 1 INFORMATION SHEET FOR QUESTIONS ABOUT THE STUDY, CONTACT: Katherine J. Murray, Stanford University, Building 120, Room 300, 415-513-6420. DESCRIPTION: You are invited to participate in a research study on computing interfaces for Windows-based PC devices. You will be asked to work through a series of tasks using a new interface paradigm. All data, including both your written responses as well as your interactions with the device, will be stored separately from any identifying information. These data will be stored in digital format on computers accessible only to the members of the project team. TIME INVOLVEMENT: Your participation in this experiment will take approximately one hour today. COMPENSATION: You will receive one hour of credit for participation in this study. SUBJECT'S RIGHTS: If you have read this form and have decided to participate in this project, please understand your participation is voluntary and you have the right to withdraw your consent or discontinue participation at any time without penalty or loss of benefits to which you are otherwise entitled. You have the right to refuse to answer particular questions. Your individual privacy will be maintained in all published and written data resulting from the study. CONTACT INFORMATION: Questions, Concerns, or Complaints: If you have any questions, concerns, or complaints about this research study, its procedures, risks, and benefits, you should ask the Protocol Director, Katherine J. Murray. You may contact her now or later at 415-513-6420 or at [email protected]. Additionally, you may contact the Faculty Sponsor, Professor Clifford Nass, at 650-723-5499. This form is yours to take with you. Protocol Approval Date: 03/26/20 Protocol Expiration Date: N/A (Exempt status)
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The Relay: Content Task Today you are going to spend some time learning about an event called “The Relay,” which took place a few weeks ago. You’ll find a good bit of information about this on the device you’ve been given by the researcher. You’ll be asked to read several articles—and fill out answers on a worksheet about The Relay. All the answers can be found in these articles. Please work quickly but be as accurate as possible. When you’ve completed your packet, please let the researcher know. The researcher should have started the task for you. Please be sure to close out by clicking Done at the bottom of the screen. You’re welcome to navigate among these pages as you’d like to. You can navigate among them by clicking on the spot on the screen next to where a content page lives. There are two pages on each side of the screen, so clicking in either the top or bottom of the right side of the screen will launch one of those pages—and so forth for all four sides of the device. There is an image of this on the next page if you’d like to refer to that at anytime.
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The Relay: What is it?
1. In what region of the country does “The Relay” take place?
2. The starting line of The Relay for the RUN teams is in which town?
3. The starting line of The Relay for the WALK teams is in which town?
4. How many miles is the RUN course?
5. How many miles is the WALK course?
6. The finish line is in which town?
7. How many people are in each team?
8. What is an example of “tagging” a van?
9. In which town does Runner 7 begin her first leg?
10. What non-profit organization is affiliated with The Relay?
11. Where was this non-profit organization started?
12. What award did this non-profit organization receive?
13. What are the first names of the 4 people who the 2010 Relay was dedicated to?
14. What unusual thing had the author realized about himself in the first paragraphs?
15. What time was the author running?
16. What was the last time the author remembered before this event occurred?
17. The author describes being “consumed with the pleasant sensation of _______ ___________.”
18. 2010 was the ___th annual Relay.
19. The 2011 Relay will take place on which weekend?
20. The Relay is modeled after what other event?
Once you have answered all these questions, please turn the page and fill out the
assessment of this task.
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PLEASE LET THE RESEARCHER KNOW WHEN YOU’VE COMPLETED THE WORKSHEET AND ASSESSMENT.
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The Terrain Please take a look at the maps of the different legs of The Relay. On your device are examples from the 36 legs—with some information about each. 6 images will be available to you on the device. Please look at each one and answer the following questions about the legs. All the answers to the questions can be found on the maps or in the accompanying text. When you’ve completed this worksheet, please let the researcher know. The researcher should have started the task for you. Please be sure to click Done when you have completely finished the task. You can move to the right, left, up, and down as well as zoom in and out on the map. Additionally you can move to the next map image or back to the previous map image by using the functions that live outside of the screen. You simply need to touch the image in the space adjacent to where the function lives. The accompanying image is a map of this.
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The Relay Legs Leg 1
1. How long is this leg?
2. What is the highest elevation of this leg?
3. Do the runner and the van follow the exact same path for this leg?
4. How hard is this leg considered?
5. If there are turns on this leg for the runner, what is the last turn? Leg 2
1. How long is this leg?
2. What is the highest elevation of this leg?
3. Do the runner and the van follow the exact same path for this leg?
4. How hard is this leg considered?
5. If there are turns on this leg for the runner, what is the last turn?
Once you have answered all these questions, please turn the page and fill out the assessment of this task.
137
Please turn the page to continue.
138
Leg 3
1. How long is this leg?
2. What is the highest elevation of this leg?
3. Do the runner and the van follow the exact same path for this leg?
4. How hard is this leg considered?
5. If there are turns on this leg for the runner, what is the last turn? Leg 4
1. How long is this leg?
2. What is the highest elevation of this leg?
3. Do the runner and the van follow the exact same path for this leg?
4. How hard is this leg considered?
5. If there are turns on this leg for the runner, what is the last turn?
Once you have answered all these questions, please turn the page and fill out the assessment of this task.
139
Please turn the page to continue.
140
Leg 5
1. How long is this leg?
2. What is the highest elevation of this leg?
3. Do the runner and the van follow the exact same path for this leg?
4. How hard is this leg considered?
5. If there are turns on this leg for the runner, what is the last turn? Leg 6
1. How long is this leg?
2. What is the highest elevation of this leg?
3. Do the runner and the van follow the exact same path for this leg?
4. How hard is this leg considered?
5. If there are turns on this leg for the runner, what is the last turn?
Once you have answered all these questions, please turn the page and fill out the assessment of this task.
141
Please let the researcher know that you are done.
142
Just one more thing. Please take a moment to fill out the following surveys! This scale consists of a number of words and phrases that describe different feelings and emotions. Read each item and then mark the appropriate answer in the space next to that word. Indicate t o what extent you have felt this way right now.
Very slightly or not at all
A little Moderately Quite a Bit Extremely
Cheerful 1 2 3 4 5 Sad 1 2 3 4 5
Active 1 2 3 4 5 Angry at Self 1 2 3 4 5
Disgusted 1 2 3 4 5 Calm 1 2 3 4 5 Guilty 1 2 3 4 5
Enthusiastic 1 2 3 4 5 Attentive 1 2 3 4 5
Afraid 1 2 3 4 5 Joyful 1 2 3 4 5
Downhearted 1 2 3 4 5 Bashful 1 2 3 4 5 Tired 1 2 3 4 5
Nervous 1 2 3 4 5 Sheepish 1 2 3 4 5 Sluggish 1 2 3 4 5 Amazed 1 2 3 4 5 Lonely 1 2 3 4 5
Distressed 1 2 3 4 5 Daring 1 2 3 4 5 Shaky 1 2 3 4 5 Sleepy 1 2 3 4 5
Blameworthy 1 2 3 4 5 Surprised 1 2 3 4 5
Happy 1 2 3 4 5 Excited 1 2 3 4 5
Determined 1 2 3 4 5 Strong 1 2 3 4 5 Timid 1 2 3 4 5 Hostile 1 2 3 4 5
143
This scale consists of a number of words and phrases that describe different feelings and emotions. Read each item and then mark the appropriate answer in the space next to that word. Indicate t o what extent you have felt this way right now.
Very slightly or not at all
A little Moderately Quite a Bit Extremely
Frightened 1 2 3 4 5 Scornful 1 2 3 4 5
Alone 1 2 3 4 5 Proud 1 2 3 4 5
Astonished 1 2 3 4 5 Relaxed 1 2 3 4 5
Alert 1 2 3 4 5 Jittery 1 2 3 4 5
Interested 1 2 3 4 5 Irritable 1 2 3 4 5 Upset 1 2 3 4 5 Lively 1 2 3 4 5
Loathing 1 2 3 4 5 Delighted 1 2 3 4 5
Angry 1 2 3 4 5 Ashamed 1 2 3 4 5 Confident 1 2 3 4 5 Inspired 1 2 3 4 5
Bold 1 2 3 4 5 At Ease 1 2 3 4 5
Energetic 1 2 3 4 5 Fearless 1 2 3 4 5
Blue 1 2 3 4 5 Scared 1 2 3 4 5
Concentrating 1 2 3 4 5 Disgusted with Self
1 2 3 4 5
Shy 1 2 3 4 5 Drowsy 1 2 3 4 5
Dissatisfied with Self
1 2 3 4 5
144
Please rate the interaction you had with this new INTERFACE using the following scale. Please consider only how you feel about what you saw on the screen and your feelings about the interactions with the program.
Not at all useful 1 2 3 4 5 Useful Annoying 1 2 3 4 5 Pleasing Confusing 1 2 3 4 5 Easy to understand Unexciting 1 2 3 4 5 Exciting Cluttered 1 2 3 4 5 Clean Boring 1 2 3 4 5 Fun
Unfriendly 1 2 3 4 5 Friendly Unoriginal 1 2 3 4 5 Creative
Makes me feel unsafe 1 2 3 4 5 Makes me feel safe Unapproachable 1 2 3 4 5 Approachable
Forgettable 1 2 3 4 5 Captivating Inconvenient 1 2 3 4 5 Convenient
Dull 1 2 3 4 5 Entertaining Unhelpful 1 2 3 4 5 Helpful
Uninspiring 1 2 3 4 5 Inspiring Unsophisticated 1 2 3 4 5 Intelligent
Pessimistic 1 2 3 4 5 Optimistic Indifferent 1 2 3 4 5 Passionate
Untrustworthy 1 2 3 4 5 Trustworthy Ordinary 1 2 3 4 5 Unique
145
Please rate the DEVICE you used on the following scale. Please rate the computer itself aside from the interactions with the interface.
Not at all useful 1 2 3 4 5 Useful Annoying 1 2 3 4 5 Pleasing Confusing 1 2 3 4 5 Easy to understand Unexciting 1 2 3 4 5 Exciting Cluttered 1 2 3 4 5 Clean Boring 1 2 3 4 5 Fun
Unfriendly 1 2 3 4 5 Friendly Unoriginal 1 2 3 4 5 Creative
Makes me feel unsafe 1 2 3 4 5 Makes me feel safe Unapproachable 1 2 3 4 5 Approachable
Forgettable 1 2 3 4 5 Captivating Inconvenient 1 2 3 4 5 Convenient
Dull 1 2 3 4 5 Entertaining Unhelpful 1 2 3 4 5 Helpful
Uninspiring 1 2 3 4 5 Inspiring Unsophisticated 1 2 3 4 5 Intelligent
Pessimistic 1 2 3 4 5 Optimistic Indifferent 1 2 3 4 5 Passionate
Untrustworthy 1 2 3 4 5 Trustworthy Ordinary 1 2 3 4 5 Unique
146
Appendix 2.4— Correlations, Dependent Variables
Correlations: # of Flicks & Duration
Correlations
ContentTask_TotalTime_Seconds_Equation
ContentTask_TotalFlick
s
MapTask_TotalTime_Seconds_Formul
a MapTask_Tot
alFlicks
Pearson Correlation
1 .106 .281* .104
Sig. (2-tailed)
.456 .043 .462
ContentTask_TotalTime_Seconds_Equation
N 52 52 52 52 Pearson Correlation
.106 1 -.015 .148
Sig. (2-tailed)
.456 .915 .296
ContentTask_TotalFlicks
N 52 52 52 52 Pearson Correlation
.281* -.015 1 .447**
Sig. (2-tailed)
.043 .915 .001
MapTask_TotalTime_Seconds_Formula
N 52 52 53 53
Pearson Correlation
.104 .148 .447** 1
Sig. (2-tailed)
.462 .296 .001
MapTask_TotalFlicks
N 52 52 53 53 *. Correlation is significant at the 0.05 level (2-tailed).
147
Correlations
ContentTask_TotalTime_Seconds_Equation
ContentTask_TotalFlick
s
MapTask_TotalTime_Seconds_Formul
a MapTask_Tot
alFlicks
Pearson Correlation
1 .106 .281* .104
Sig. (2-tailed)
.456 .043 .462
ContentTask_TotalTime_Seconds_Equation
N 52 52 52 52 Pearson Correlation
.106 1 -.015 .148
Sig. (2-tailed)
.456 .915 .296
ContentTask_TotalFlicks
N 52 52 52 52 Pearson Correlation
.281* -.015 1 .447**
Sig. (2-tailed)
.043 .915 .001
MapTask_TotalTime_Seconds_Formula
N 52 52 53 53 Pearson Correlation
.104 .148 .447** 1
Sig. (2-tailed)
.462 .296 .001
MapTask_TotalFlicks
N 52 52 53 53 *. Correlation is significant at the 0.05 level (2-tailed).
**. Correlation is significant at the 0.01 level (2-tailed).
148
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