INFO 203 Week #2 1

IT For EngineersInformation Gathering &

Prototyping

INFO 203

Dr. Jennifer Booker

Introduction

Now that we’ve had an overview of the development life cycle, we’ll focus on activities to gather requirements both interactively (chapter 4) and unobtrusively (chapter 5)

Then we’ll examine prototyping, and skip Agile modeling (chapter 6)

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Chapter 4 – interactive methods

Three major methods for collecting requirements interactively are: Interviewing Joint application design (JAD) Survey questionnaires

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Interviews

Preparation is key to giving good interviews Look for your own biases, such as regarding

The type of legacy system The educational level of the users The intelligence of the users The type of work being done And anything else which might be a factor

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Interviews

Make sure the purpose and scope of the interview are clear What kinds of information are you looking for? Whom do you need to interview? How much time do you need? Are the interviewees all in one location?

Keep in mind that opinions are also important information, not just facts

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Interviews

Users may have strong feelings about what’s good and bad about the existing system, which can feed the problems and opportunities analysis Also gives insight into the organizational culture

Look for the users’ objectives or goals You want to interview to be a comfortable

experience for the subject, but you need to keep control

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Interview Preparation

To prepare for an interview Read background material Establish interviewing objectives Decide whom to interview, e.g. people in

different roles Prepare the interviewee – call or email in advance Decide on question types and structure

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Question Types

Questions can be open-ended or closed An open-ended question encourages a

long response What do you think about …? What’s your opinion about …? Please explain how you …? What are the biggest problems …? Could you tell me why …?

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Question Types

Closed questions encourage a Yes or No answer, or a very short response Who receives …? Do you like …? Do you want …? How many times a week …?

Keep in mind they take little time to answer compared to open-ended questions

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Question Types

Open questions get more detail and help build trust with the interviewee

Closed questions cover more subjects, keep control better, and are easier to manage

Open questions may be followed up with a probe question Why? Can you give me an example? Will you please explain that for me?

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Organizing Questions

Just like logic can be inductive or deductive, the structure of interview questions can follow similar patterns The pyramid approach goes from specific

questions to general ones (inductive) The funnel approach goes from general to

specific (deductive) A diamond approach goes from specific, to

general, then back to specific

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Organizing Questions

After the interview, write a report on it to capture key information It’s common for someone to write down

responses during an interview, the avoid losing key observations

Compare results with the objectives of the interview

If needed, contact interviewee for clarification or get missing info from later interviews

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Joint Application Design

Joint Application Design (or Development) (JAD) is uses a group setting to resolve some key aspects of the system – often requirements and/or high level design

Good to use when there are strongly conflicting views or priorities, or urgent need for a new perspective

Otherwise generally not worth while, since it tends to be expensive

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Joint Application Design

JAD typically involves 8-12 people representing various users and technical specialties, including Executive sponsor starts and finishes the session At least one IS/IT analyst should be present, but

primarily for a sanity check on possible solutions The session leader is typically an outside

consultant, trained in leading JAD sessions Observers may attend A scribe is used to record results (take minutes)

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Joint Application Design

JAD sessions are typically held off-site (away from the normal office) to help people focus For design work, prototyping tools may be needed

JAD sessions typically last 2-4 days; they’re too intense to last much longer Attendees need 100% commitment to the session

The scope of a JAD session needs to be clearly defined; a formal agenda is common

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Joint Application Design

JAD can save time over interviews, reduce the cycle time, improve ownership in the decisions reached, and finally, it can encourage more creative design work

OTOH, JAD requires a noticeable time commitment, it relies on good preparation and follow-up, and the organizational culture needs to support its approach

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Questionnaires

Questionnaires (surveys) can help determine how people in the organization are affected by the existing system Helps determine if a view found in an interview is

widespread or not Or could be used to help identify problem areas

before interviews are conducted If you use closed questions, the responses

can be quantified much more easily

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Questionnaires

Questionnaires are good to use: If the respondents are widely distributed

geographically You want statistics on certain viewpoints You want an overview of the situation before

further investigation, or If you want a survey of problems with the

existing system to follow up with interviews

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Questionnaires

The questions used for questionnaires need to be more carefully thought out than for an interview You need to decide if open-ended questions

should have some structure (e.g. the top three problems), instead of just an open question about problems

If you want quantifiable information, you need to structure the response section to give consistent responses

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Questionnaires

Closed questions typically need to be answered by checking a box, circling a response, or entering numbers

The choice of wording is very important Use local terminology Keep wording simple, but don’t talk down to

the audience Keep questions short

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Questionnaires

Avoid bias in wording Why do you hate the existing system?

[Like a psychiatrist asking “Why do you hate your mother?”]

Make sure wording is accurate Make sure the audience can answer

the questions – is it in the scope of their knowledge?

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Scales in Questionnaires

Consider how you are measuring responses What kind of scale are you creating?

Do you find the help desk staff courteous?1 = Yes, 2 = No

How courteous do you find the help desk staff? (Rate on 1-100, 1 = not at all, 100 = extremely)

Between those extremes, the 5-point Likert scale is common (e.g. 1 = not at all, 5 = extremely) or maybe 7-point

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Designing Questionnaires

The approaches for designing a questionnaire can follow the same principles as an interview – you just have no flexibility to adapt it based on the responses Put questions important to the respondent

first (why?) Cluster similar topics together Introduce controversial questions later

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Questionnaires

Administering (giving) a questionnaire can be done many ways Hand them out at a meeting, and collect

them immediately Collect finished questionnaires in a drop box Provide instructions and return postage so they

can mail the completed questionnaire back Email the questionnaire Post the questionnaire on a web site

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Questionnaires

Keep in mind that a questionnaire could be more valuable (objective) if it’s anonymous Don’t include questions that would compromise

that objectivity Who is your manager? How long have you been working here? What is your age? What is your gender?

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Chapter 5 - Unobtrusive Methods

Unobtrusive methods for gathering information include Sampling Investigation Observation

These should be used in conjunction with one or more interactive methods

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Sampling

Sampling refers to selecting a subset of the whole subject (the population) in order to deduce information about the population

In this context, we might want to know Which of our system’s inputs and outputs we

should examine? or Which people we should interview? We could also sample existing data to use for

test cases

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Sampling

Sampling helps speed up data collection, thereby reducing cost; but can also reduce bias and improve effectiveness

To create a sample, need to Determine data to be collected Determine population to be sampled Choose type of sample Calculate sample size

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Types of Samples

A systematic sample just takes every nth person or record

A simple random sample is the most common kind for polling Use some objective means to generate a

random number, and include that person or record in your sample

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Types of Samples

Stratified samples look for types of groups in the population (e.g. Windows, Mac, or Android users), then takes a simple random sample within each stratum

A clustered sample is based on choosing some number of clusters of information (e.g. sites) to represent all clusters, and taking a random sample within the selected clusters

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Sample Size

Determine what attribute you want to measure

Finding a sample size is weird, since you have to start by guessing what the answer is Select a value for ‘p’, the proportion of things

which will have the thing you want (e.g. percent of people who will vote for X) For the worst case (and largest sample size),

choose p = 0.50

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Sample Size

Choose the acceptable margin for error, ‘i’ (typically 3-5%, a.k.a. interval estimate)

Choose the confidence level in your result, and look up the corresponding ‘z’ value

Find P = i/z Then the sample size, ‘n’, is

n = p(1-p) / P2 + 1

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Critical Z values

Confidence Level 2-sided critical Z

80% 1.28

90% 1.645

95% 1.96

99% 2.57

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Sample Size Example

So if we want a worst case sample size for 3% confidence interval, and 95% level of confidence, the simple random sample size is p = 0.50 so p(1-p) = .5*.5 = 0.25 i = 0.03 Z = 1.96 based on the 95% level of confidence P = i/z = 0.03/1.96 = 0.01531

n = p(1-p) / P2 + 1 = 0.25 / (0.01531)2 + 1 = 1068

We need a sample size of 1068

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Sample Size Caveat

The previous formula for ‘n’ assumes a very large population (in the 1000’s)

To correct for a small population, ‘N’, or if ‘i’ is extremely small, use this mess n = [N*Z2*p*(1-p)] / [N*i2 + Z2*p*(1-p)]

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Investigation

Investigation in this context refers to examining the existing system, both quantitative and qualitative documents Quantitative Investigation Qualitative Investigation

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Quantitative Investigation

Existing reports may be examined to determine several things What existing reports will need to be created

by the new system? How has data been entered into the system? What are the current performance and process

goals or objectives? How well have they been doing in meeting

those goals?

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Quantitative Investigation

Examples of quantitative reports might include reports used for decision making Status of inventory Production quality Amount of sales Profitability Staffing reports

These typically look for trends and problems

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Quantitative Investigation

Performance reports might compare actual performance to the planned or goal values Could look for completeness of such reports – are

all areas reporting their performance? General records can show individual

data updates Such as payment records, invoices, timesheets Check for completeness, accuracy, and

opportunities for improvements

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Quantitative Investigation

Data capture forms are generally the lowest level of data Great for understanding the start of business

processes Look for unofficial and informal forms in use Document how the forms are used

What is the business process flow? Who fills out each form? Who approves each form? Is their use mandatory?

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Quantitative Investigation

Check for consistency between the forms and the existing database

Are some forms never used? Are there variations of the same form used? Are there multiple places to find a form?

Data capture forms are often the most frequently used work products, so improvements here can pay off a lot

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Qualitative Investigation

Qualitative documents include any kind of relatively unstructured text – memos, letters, procedures, fliers, web sites, etc.

These often tell a lot about the company culture and document expectations Is the company portrayed as a machine?

Family? Corporation? Team? Is there a sense of humor? Internal competition?

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Qualitative Investigation

Memos, for example, can tell a lot from their distribution and tone

What’s most important to the organization? Safety? Profit? Happy customers? Happy

stockholders? Quality? Market share? Signs posted in common areas can

answer this

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Qualitative Investigation

What about their web site? What kind of metaphors does it use? Is it clear? Is it interactive?

Look at their manuals, procedures & policies Are they current? Are they used by anyone?

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Observing Behavior

Another key way to obtain information unobtrusively is to observe people doing their jobs

Need to get their managers’ approval, and explain what you’re doing

Can observe people at different levels – data entry people, analysts, managers, etc. Note this differs from the text

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Observing Behavior

At low levels of the organization, observation can help answer key questions about organizational culture and processes How often are different types of tasks done? Are they following the stated procedures? What do they do when something goes wrong? In what order do they do things (e.g. data entry)? For managers, how do they make decisions?

This can help outline procedures as they occur

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Observing Behavior

Can model behavior by treating each person as an actor, and summarize the steps each follows in their “script” How do they gather data? Read, observe, ask? What decisions do they make? Whom do they tell

about those decisions?

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Observing Environment

Another aspect of observation is to look at the work environment

The STROBE method refers to “STRuctured Observation of the Environment”

Decision makers often define the work environment, so it’s helpful to see what kind of world they have created Like the director of a movie

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Observing Environment

What does their office location say? Do they have corner offices? Are they located with other managers,

or with their staff? Does their desk placement encourage

communication? Demonstrate power? Where do they store data? Do they have a

lot of it or a little?

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Observing Environment

Do they appear to use their PC and/or PDA often?

Do they get information from outside publications or the Web?

Do the office’s lighting and colors encourage communication, or detailed work?

What do their clothes say about them? Is there a clear hierarchy based on clothes?

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Observing Environment

Using STROBE can help understand the priorities of a user If they don’t use a PC often, maybe reports

should be formatted for paper instead of Web If they don’t care about looking at data, then the

ability to “drill down” in reports might not be urgent If they are very hierarchical, that could imply a

limit on the distribution of reports And so on…

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Chapter 6 – Agile & Prototyping

Prototyping is often a good tool for clarifying requirements of a system, and/or resolving risks associated with developing a system

It generally helps determine the functional requirements for users, especially associated with the user interface

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Prototyping

There are four major types of prototype Patched-up prototype Nonoperational prototype First-of-a-series prototype Selected features prototype

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Patched-up Prototype

This is a functional prototype, but it works very crudely or inefficiently

Based on the proof of concept prototype – slap something together quickly that will work well enough to tell if the idea is technically feasible

Also can be used to determine if a given technology is compatible with the system

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Nonoperational Prototype

This is using a prototype more like a storyboard

The interfaces are developed, but there’s no actual code behind them Like the façade of a building used on a movie set

Only helps with functional requirements, and the general look and feel of the system

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First-of-a-series Prototype

This is the development of a fully functional pilot version of the system, in the hopes that it will be close to the final product

Based on this prototype, the system is refined and then produced en masse

Might be helpful for a physical installation, such as a MAC terminal or information kiosk

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Selected Features Prototype

The last kind of prototype is used to completely develop a portion of the system

This avoids over committing to the design before a user can approve its approach

Works well with an iterative life cycle Develop the core of the system with a couple

of working features Then see if the users like it before the rest of

the system is added

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Prototyping

Notice for two kinds of prototype, the prototype is not like the final product Patched-up prototype Nonoperational prototype

The other two kinds of prototype are similar to the final product First-of-a-series prototype Selected features prototype

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Prototyping vs. the SDLC

Some propose that prototyping can replace the development life cycle

This isn’t practical in most cases, because Developing a First-of-a-series prototype is about

the same effort as following the SDLC to create the same thing

Prototypes often use impromptu designs, which couldn’t meet nonfunctional system requirements (performance, security, etc.)

Prototyping may stop the design process prematurely

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Prototyping Guidelines

Guidelines for developing a “Selected features prototype” include Estimate costs for creating the desired parts

of the system Work in manageable modules Build the prototype quickly Modify the prototype iteratively; minimize coupling Focus on the user interface; or users will hate

the system from the beginning

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Prototyping Disadvantages

It can be hard to distinguish between finishing prototyping, and starting development of the real system Need to make sure the scope of prototyping

is clear Users may view the prototype as the

end product Users may wonder why the real system

takes so much longer than the prototype

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Prototyping Advantages

Prototyping gives an opportunity to ensure that the users’ needs are clearly translated into system requirements

Prototyping helps clarify if the project is reasonably close to the intended scope Can stop funding the project if it isn’t fixable

Prototyping gives visibility into the developer’s design concept, which is often reassuring to the customer

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Prototyping with COTS

COTS (Commercial, Off-The-Shelf) products are used in almost every information system You don’t design custom motherboards, operating

systems, database management systems, etc. – instead you use a commercially available product

Though an extreme example, even ERP applications such as SAP and PeopleSoft could be considered COTS products, even though they are heavily customized

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Users and Prototyping

Analysts need honest, realistic involvement from users, or prototyping will have no benefit

Users play a key role in prototyping Users should experiment with the prototype Give qualitative feedback – do they like it,

and why or why not? Give quantitative feedback – what features

are missing, hard to use, counter-intuitive, not needed, etc.? Don’t ask for the impossible!

Agile Modeling

Skip this section (pages 157 to the end of the chapter)

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