Människa-dator interaktion B, 5p

Kognitionsvetenskap C, 5pUbiquitous Computing C, 5p

Människa-dator interaktion II D, 5pNya medier D, 5p

What is Interaction Design?

What is interaction design?

• Designing interactive products to support people in their everyday and working lives

– Sharp, Rogers and Preece (2002)

• The design of spaces for human communication and interaction

– Winograd (1997)

Goals of interaction design

• Develop usable products– Usability means easy to learn,

effective to use and provide an enjoyable experience

• Involve users in the design process

Example of bad and good design– Elevator controls and labels on the bottom

row all look the same, so it is easy to push a label by mistake instead of a control button

– People do not make same mistake for the labels and buttons on the top row. Why not?

From: www.baddesigns.com

Why is this vending machine so bad?

• Need to push button first to activate reader

• Normally insert bill first before making selection

• Contravenes well known convention

From: www.baddesigns.com

What to design

• Need to optimise the interactions users have with a product– Such that they match the users activities

and needs

• Need to take into account:– Who the users are– What activities are being carried out– Where the interaction is taking place

Understanding users’ needs

– Need to take into account what people are good and bad at

– Consider what might help people in the way they currently do things

– Listen to what people want and get them involved

– Use tried and tested user-based methods

Activity

• How does making a call differ when using a:– Cell phone– Public phone box?

• Consider the kinds of user, type of activity and context of use

What is an interface?

?

Evolution of HCI ‘interfaces’• 50s - Interface at the hardware level for engineers -

switch panels• 60-70s - interface at the programming level - COBOL,

FORTRAN• 70-90s - Interface at the terminal level - command

languages • 80s - Interface at the interaction dialogue level - GUIs,

multimedia• 90s - Interface at the work setting - networked systems,

groupware • 00s - Interface becomes pervasive

– RF tags, Bluetooth technology, mobile devices, consumer electronics, interactive screens, embedded technology

From HCI to Interaction Design• Human-computer interaction (HCI) is:

“concerned with the design, evaluation and implementation of interactive computing systems for human use and with the study of major phenomena surrounding them” (ACM SIGCHI, 1992, p.6)

• Interaction design (ID) is: “the design of spaces for human communication and interaction”

– Winograd (1997)

• Increasingly, more application areas, more technologies and more issues to consider when designing ‘interfaces’

Relationship between ID, HCI and other fields

Interdisciplinary fields (e.g HCI, CSCW)

Design practices(e.g. graphic design)

Academicdisciplines(e.g. computer science,psychology)

InteractionDesign

Relationship between ID, HCI and other fields

• Academic disciplines contributing to ID: – Psychology– Social Sciences– Computing Sciences– Engineering– Ergonomics– Informatics

Relationship between ID, HCI and other fields

• Design practices contributing to ID:– Graphic design– Product design– Artist-design– Industrial design– Film industry

Relationship between ID, HCI and other fields

• Interdisciplinary fields that ‘do’ interaction design:

– HCI– Human Factors– Cognitive Engineering– Cognitive Ergonomics– Computer Supported Co-operative Work– Information Systems

How easy is it to work in multidisciplinary teams?

• More people involved in doing interaction design the more ideas and designs generated…but…

• The more difficult it can be to communicate and progress forwards the designs being created

Interaction design in business• Increasing number of ID consultancies, examples of well

known ones include:– Nielsen Norman Group: “help companies enter the

age of the consumer, designing human-centered products and services”

– Swim: “provides a wide range of design services, in each case targeted to address the product development needs at hand”

– IDEO: “creates products, services and environments for companies pioneering new ways to provide value to their customers”

What do professionals do in the ID business?

• interaction designers - people involved in the design of all the interactive aspects of a product

• usability engineers - people who focus on evaluating products, using usability methods and principles

• web designers - people who develop and create the visual design of websites, such as layouts

• information architects - people who come up with ideas of how to plan and structure interactive products

• user experience designers - people who do all the above but who may also carry out field studies to inform the design of products

Core characteristics ofinteraction design

• Users should be involved through the development of the project

• Specific usability and user experience goals need to be identified, clearly documented and agreed at the beginning of the project

• Iteration is needed through the core activites...

Core activities

• Identify needs and establish requirements

• Develop alternative designs

• Build interactive prototypes that can be communicated and assessed

• Evaluate what is being built throughout the process

Usability goals

• Effective to use (Man kan göra det man vill göra.)

• Efficient to use (Bra invävnad av funktionaliteten i människans pågående aktivitet, dvs. minimalt merarbete.)

• Safe to use• Have good utility (Man kan göra det man vill

göra på det sätt man vill.

• Easy to learn• Easy to remember how to use

User experience goals

– Satisfying - rewarding– Fun - support creativity– Enjoyable - emotionally fulfilling– Entertaining …and more– Helpful– Motivating– Aesthetically pleasing

Usability and user experience goals

• How do usability goals differ from user experience goals?

• Are there trade-offs between the two kinds of goals?– e.g. can a product be both fun and safe?

• How easy is it to measure usability versus user experience goals?

Design principles

• Generalizable abstractions for thinking about different aspects of design

• The do’s and don’ts of interaction design

• What to provide and what not to provide at the interface

• Derived from a mix of theory-based knowledge, experience and common-sense

Visibility• This is a control panel for an

elevator. • How does it work?• Push a button for the floor you

want?

• Nothing happens. Push any other button? Still nothing. What do you need to do?

It is not visible as to what to do!

From: www.baddesigns.com

Visibility…you need to insert your room card in the slot by the buttons to get the elevator to work!

How would you make this action more visible?

• make the card reader more obvious• provide an auditory message, that says what to do

(which language?)• provide a big label next to the card reader that flashes

when someone enters

• make relevant parts visible• make what has to be done obvious

Feedback

• Sending information back to the user about what has been done

• Includes sound, highlighting, animation and combinations of these

– e.g. when screen button clicked on provides sound or red highlight feedback:

“ccclichhk”

Constraints

• Restricting the possible actions that can be performed

• Helps prevent user from selecting incorrect options

• Three main types (Norman, 1999)– physical– cultural – logical

Physical constraints

• Refer to the way physical objects restrict the movement of things– E.g. only one way you can insert a key into

a lock

• How many ways can you insert a CD or DVD disk into a computer?

• How physically constraining is this action?

• How does it differ from the insertion of a floppy disk into a computer?

Logical constraints

• Exploits people’s everyday common sense reasoning about the way the world works

• An example is they logical relationship between physical layout of a device and the way it works as the next slide illustrates

Logical or ambiguous design?

• Where do you plug the mouse?

• Where do you plug the keyboard?

• top or bottom connector?

• Do the color coded icons help?

From: www.baddesigns.com

How to design them more logically

(i) A provides direct adjacent mapping between icon and connector

(ii) B provides color coding to associate the connectors with the labels

From: www.baddesigns.com

Cultural constraints

• Learned arbitrary conventions like red triangles for warning

• Can be universal or culturally specific

Which are universal and which are culturally-specific?

Mapping

• Relationship between controls and their movements and the results in the world

• Why is this a poor mapping of control buttons?

Mapping

• Why is this a better mapping?

• The control buttons are mapped better onto the sequence of actions of fast rewind, rewind, play and fast forward

Consistency

• Design interfaces to have similar operations and use similar elements for similar tasks

• For example:– always use ctrl key plus first initial of the

command for an operation – ctrl+C, ctrl+S, ctrl+O

• Main benefit is consistent interfaces are easier to learn and use

Affordances: to give a clue

• Refers to an attribute of an object that allows people to know how to use it– e.g. a mouse button invites pushing, a door handle

affords pulling

• Norman (1988) used the term to discuss the design of everyday objects

• Since has been much popularised in interaction design to discuss how to design interface objects– e.g. scrollbars to afford moving up and down, icons

to afford clicking on

What does ‘affordance’ have to offer interaction design?

• Interfaces are virtual and do not have affordances like physical objects

• Norman argues it does not make sense to talk about interfaces in terms of ‘real’ affordances

• Instead interfaces are better conceptualised as ‘perceived’ affordances– Learned conventions of arbitrary mappings between

action and effect at the interface– Some mappings are better than others

Activity

– Physical affordances: How do the following physical objects

afford? Are they obvious?

Activity

– Virtual affordancesHow do the following screen objects

afford?What if you were a novice user?Would you know what to do with them?

Usability principles

• Similar to design principles, except more prescriptive

• Used mainly as the basis for evaluating systems

• Provide a framework for heuristic evaluation

Usability principles (Nielsen 2001)

• Visibility of system status• Match between system and the real world• User control and freedom• Consistency and standards• Help users recognize, diagnose and recover from

errors• Error prevention• Recognition rather than recall• Flexibility and efficiency of use• Aesthetic and minimalist design• Help and documentation

Understanding and conceptualizing interaction

Recap• HCI has moved beyond designing interfaces

for desktop machines• About extending and supporting all manner

of human activities in all manner of places• Facilitating user experiences through

designing interactions• Make work effective, efficient and safer• Improve and enhance learning and training• Provide enjoyable and exciting entertainment• Enhance communication and understanding• Support new forms of creativity and expression

Understanding the problem space

– What do you want to create?– What are your assumptions?– Will it achieve what you hope it will?

A framework for analysing the problem space

• Are there problems with an existing product?

• Why do you think there are problems?• Why do you think your proposed ideas

might be useful?• How would you see people using it with

their current way of doing things?• How will it support people in their

activities?• Will it really help them?

An example

• What were the assumptions made by cell phone companies when developing WAP services?

• Was it a solution looking for a problem?

Assumptions: realistic or wish-list?

• People want to be kept informed of up-to-date news wherever they are - reasonable

• People want to interact with information on the move - reasonable

• People are happy using a very small display and using an extremely restricted interface - not reasonable

• People will be happy doing things on a cell phone that they normally do on their PCs (e.g. surf the web, read email, shop, bet, play video games) - reasonable only for a very select bunch of users

From problem space to design space

• Having a good understanding of the problem space can help inform the design space– e.g. what kind of interface, behavior,

functionality to provide• But before deciding upon these it

is important to develop a conceptual model

Conceptual model

• Need to first think about how the system will appear to users (i.e. how they will understand it)

• A conceptual model is a high level description of:– “the proposed system in terms of a set of

integrated ideas and concepts about what it should do, behave and look like, that will be understandable by the users in the manner intended”

First steps in formulating a conceptual model

• What will the users be doing when carrying out their tasks?

• How will the system support these?• What kind of interface metaphor, if any,

will be appropriate?• What kinds of interaction modes and

styles to use? Always keep in mind when making design decisions how the user will understand the underlying conceptual model

Conceptual models

• Many kinds and ways of classifying them

• Here we describe them in terms of core activities and objects

• Also in terms of interface metaphors

Conceptual models based on activities

• Giving instructions– issuing commands using keyboard and function

keys and selecting options via menus

• Conversing– interacting with the system as if having a

conversation

• Manipulating and navigating– acting on objects and interacting with virtual

objects

• Exploring and browsing– finding out and learning things

1. Giving instructions• Where users instruct the system and tell it

what to do– e.g. tell the time, print a file, save a file

• Very common conceptual model, underlying a diversity of devices and systems– e.g. CAD, word processors, VCRs, vending

machines

• Main benefit is that instructing supports quick and efficient interaction– good for repetitive kinds of actions performed

on multiple objects

2. Conversing• Underlying model of having a conversation

with another human

• Range from simple voice recognition menu-driven systems to more complex ‘natural language’ dialogues

• Examples include timetables, search engines, advice-giving systems, help systems

• Recently, much interest in having virtual agents at the interface, who converse with you, e.g. Microsoft’s Bob and Clippy

Pros and cons of conversational model

• Allows users, especially novices and technophobes, to interact with the system in a way that is familiar– makes them feel comfortable, at ease and less scared

• Misunderstandings can arise when the system does not know how to parse what the user says– e.g. child types into a search engine, that uses natural

language the question:“How many legs does a centipede have?” and the

system responds:

Y o u a s k e d : H o w m a n y l e g s d o e s a c e n t i p e d e h a v e ? J e e v e s k n o w s t h e s e a n s w e r s : W h e r e c a n I fi n d a d e fi n i t i o n f o r t h e m a t h t e r m l e g ? W h e r e c a n I fi n d a c o n c i s e e n c y c l o p e d i a a r t i c l e o n ? c e n t i p e d e s ? W h e r e c a n I s e e a n i m a g e o f t h e h u m a n a p p e n d i x ? W h y d o e s m y l e g o r o t h e r l i m b f a l l a s l e e p ? W h e r e c a n I fi n d a d v i c e o n c o n t r o l l i n g t h e g a r d e n p e s t ? m i l l i p e d e s a n d c e n t i p e d e s ? W h e r e c a n I fi n d r e s o u r c e s f r o m B r i t a n n i c a . c o m o n l e g ?

3. Manipulating and navigating

• Involves dragging, selecting, opening, closing and zooming actions on virtual objects

• Exploit’s users’ knowledge of how they move and manipulate in the physical world

• Exemplified by (i) what you see is what you get (WYSIWYG) and (ii) the direct manipulation approach (DM)

• Shneiderman (1983) coined the term DM, came from his fascination with computer games at the time

Core principles of DM

• Continuous representation of objects and actions of interest

• Physical actions and button pressing instead of issuing commands with complex syntax

• Rapid reversible actions with immediate feedback on object of interest

Why are DM interfaces so enjoyable?

• Novices can learn the basic functionality quickly• Experienced users can work extremely rapidly to

carry out a wide range of tasks, even defining new functions

• Intermittent users can retain operational concepts over time

• Error messages rarely needed• Users can immediately see if their actions are

furthering their goals and if not do something else• Users experience less anxiety• Users gain confidence and mastery and feel in control

What are the disadvantages with DM?

• Some people take the metaphor of direct manipulation too literally

• Not all tasks can be described by objects and not all actions can be done directly

• Some tasks are better achieved through delegating– e.g. spell checking

• Can become screen space ‘gobblers’• Moving a mouse around the screen can be slower

than pressing function keys to do same actions

4. Exploring and browsing

• Similar to how people browse information with existing media (e.g. newspapers, magazines, libraries, pamphlets)

• Information is structured to allow flexibility in way user is able to search for information– e.g. multimedia, web

Conceptual models based on objects

• Usually based on an analogy with something in the physical world

• Examples include books, tools, vehicles

• Classic: Star Interfacebased on officeobjects

Johnson et al (1989)

Another classic: the spreadsheet (Bricklin)

• Analogous to ledger sheet

• Interactive and computational

• Easy to understand• Greatly extending

what accountants and others could do

www.bricklin.com/history/refcards.htm

Which conceptual model is best?

• Direct manipulation is good for ‘doing’ types of tasks, e.g. designing, drawing, flying, driving, sizing windows

• Issuing instructions is good for repetitive tasks, e.g. spell-checking, file management

• Having a conversation is good for children, computer-phobic, disabled users and specialised applications (e.g. phone services)

• Hybrid conceptual models are often employed, where different ways of carrying out the same actions is supported at the interface - but can take longer to learn

Interface metaphors

• Interface designed to be similar to a physical entity but also has own properties– e.g. desktop metaphor, web portals

• Can be based on activity, object or a combination of both

• Exploit user’s familiar knowledge, helping them to understand ‘the unfamiliar’

• Conjures up the essence of the unfamiliar activity, enabling users to leverage of this to understand more aspects of the unfamiliar functionality

Benefits of interface metaphors

• Makes learning new systems easier• Helps users understand the

underlying conceptual model• Can be very innovative and enable

the realm of computers and their applications to be made more accessible to a greater diversity of users

Problems with interface metaphors

• Break conventional and cultural rules– e.g. recycle bin placed on desktop

• Can constrain designers in the way they conceptualize a problem space

• Conflict with design principles• Forces users to only understand the system in

terms of the metaphor• Designers can inadvertently use bad existing

designs and transfer the bad parts over• Limits designers’ imagination in coming up with

new conceptual models

Conceptual models: from interaction mode to style

• Interaction mode: – what the user is doing when interacting with

a system, e.g. instructing, talking, browsing or other

• Interaction style:– the kind of interface used to support the

mode, e.g. speech, menu-based, gesture

Many kinds of interaction styles available…

• Command• Speech• Data-entry• Form fill-in• Query• Graphical• Web• Pen• Augmented reality• Gesture and even...

Interacting via GPS enabled cell phone…

• Drawing an elephant by walking round the streets of a city (or other mode of transport) and entering data points along the way via the cell phone

• Example: Brighton and Hove(UK) by J. Wood by foot, track length 11.2km (see www.gpsdrawing.com for more examples)

Making art by recording where walking in a city

Which interaction style to choose?

• Need to determine requirements and user needs

• Take the budget and other constraints into account

• Also will depend on suitability of technology for activity being supported

• This topic will be covered more later when discuss how to actually design conceptual models

Interaction paradigms

• Another form of inspiration for conceptual models

• From the desktop to ubiquitous computing (embedded in the environment)

Examples of new paradigms

• Ubiquitous computing (mother of them all)

• Pervasive computing• Wearable computing• Tangible bits• Augmented reality

– and many more….

Summary points

• Important to have a good understanding of the problem space

• Fundamental aspect of interaction design is to develop a conceptual model

• Interaction modes and interface metaphors provide a structure for thinking about which kind of conceptual model to develop

• Interaction styles are specific kinds of interfaces that are instantiated as part of the conceptual model

• Interaction paradigms can also be used to inform the design of the conceptual model