Chapter 4 - Requirement Determination
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Transcript of Chapter 4 - Requirement Determination
Chapter 4:Requirements Determination
Key Ideas
• Goal of the analysis phase:– Truly understand the requirements of the new
system– Develop a system that addresses them -- or decide
a new system isn’t needed.
• The line between systems analysis and systems design is very blurry
Key Ideas
• The first challenge is finding the right people to participate.
• The second challenge is collecting and integrating the information
Requirements
What is a Requirement
• Business Requirement– Statement of what the system must do– Focus on what the system must do, not how to do
it
• There are 2 kinds of requirements– Functional– Nonfunctional
Functional Requirement
• Defines the functions the system must carry out
• Specifies the process that must be performed• Examples:– Must search for inventory– Must perform these calculations– Must produce a specific report
Nonfunctional Requirements
• Deals with how the system behaves• Operational – Physical/technical environment• Performance – Speed and reliability• Security – Who can use the system• Cultural & Political – Company policies, legal
issues
Requirements Definition
• Report that lists the functional and nonfunctional requirements
• All requirements must be traceable back to business requiremets
THE ANALYSIS PROCESS
Analysis Across Areas
• Analysis of the IS system is:– A business task– An IT task
• Need to balance expertise of users and analysts
The SDLC Process
Three Steps of the Analysis Phase
• Understanding the “As-Is” system• Identifying improvement opportunities• Developing the “To-Be” system concept
Three Steps of the Analysis Phase
• Understanding the “As-Is” system– To-Be derived from As-Is– Can’t focus just on what users want, need to
understand what they need– Can’t focus just on dry analysis
need to listen to users’ experience
Three Steps of the Analysis Phase
• Identifying improvement opportunities– Need business and technology skills– Business skills• Improvements in business processes
– improve what we do
• Technology skills– improve how we do it
Three Steps of the Analysis Phase
• Developing the “To-Be” system concept– Starts out as a fuzzy set of possible improvement
ideas– Refined into a viable system concept– Analysis ends with a system proposal– Proposal presented to approval committee in the
form of a system walk-through
Proposal Outline
• Table of contents• Executive summary• System request (from chapter 2)• Work plan (from chapter 3)• Analysis strategy
– Summary of analysis tasks from this chapter
• Recommended system– Summary of system concept with justification– Possibly different alternatives
Proposal Outline (cont’d)
• Feasibility analysis (from chapter 2) • Behavioral and structural models
(from chapters 5, 6, 7)• Appendices
Survey results, interviews, industry reports, potential design issues etc.Anything needed to support recommendation
Three Fundamental Analysis Strategies
• BPA– Business process automation
• BPI– Business Process Improvement
• BPR– Business Process Reengineering
BUSINESS PROCESS AUTOMATION (BPA)
Business Process Automation
• Makes almost no changes to business processes– Just makes them more efficient
• Improves efficiency by automating the business processes
• Least impact on users– They do the same things, just more efficiently
1. (BPA) Understanding the As-Is System
• Much effort spent here– To-Be system continues to support As-Is system– Will be doing essentially the same things– Build detailed behavioral and structural models• To document As-Is system
2. (BPA) Identifying Improvement Opportunities
• Most improvements come from problems in the current system
• Two techniques for identifying improvements:– Problem Analysis– Root Cause Analysis
Problem Analysis
• Problem Analysis– Most commonly used– Asks users to identify problems and solutions (users
love to do this anyway)– Very good at improving users’ efficiency– But Rarely finds significant monetary benefits
Root Cause Analysis
• Identify symptoms• Trace each back to
its causes
Symptoms
ROOT CAUSES
Symptoms
Root Cause Analysis
• Root Cause Analysis– Tracing symptoms to their causes– Problem analysis focuses on solutions to symptoms
of problems– Root cause analysis focuses on the problems
themselves– Generate list of all problems– Prioritize the list– Tracing symptoms to their causes
Root Cause Analysis
• Root Cause Analysis– Users generate list of problems with As-Is system– Prioritize the list– Generate all possible root causes– Investigate each, until true root cause is identified– Look for root causes that fix more than one problem
Root Cause Analysis Example
3. (BPA) Developing To-Be System Concept
• To-Be system is quite similar to As-Is system– No real change is business processes– Models of To-Be system not much different from As-
Is system– Often models are just copied and small changes are
made
BUSINESS PROCESS IMPROVEMENT (BPI)
Business Process Improvement
• Goal is to improve the business processes• Change what the users do,
not just how efficiently they do it• Changes to business process must be decided
first• Decisions to change the business processes
cannot be made by the analyst
1. (BPI) Understanding the As-Is System
• Still need to spend significant effort to understand As-Is system– The new system will support most of the As-Is
system– New system will do many of the same things– But some processes will be very different
2. (BPI) Identifying Improvement Opportunities
• Focus considerable effort here– Looking for improvements to business processes– Users and managers
actively seek out new business ideas and opportunities
2. (BPI) Identifying Improvement Opportunities
• Four techniques for identifying improvement opportunities
1. Duration Analysis2. Activity-Based Costing3. Informal Benchmarking4. Formal Benchmarking
Duration Analysis
• Calculate time for each process step• Calculate time for overall process• Compare the two
If sum(time for each individual step) is much less than
sum (time for overall process)– Then there is a problem
• Will need to develop– Process integration or– Parallelization
Duration Analysis
• When many different people work on small parts of the overall process
• Process integration– Change fundamental process so fewer people work
on the input
• Parallelization– Change the process so the people can do their part
at the same time
Activity-Based Costing
• Calculate cost of each process step• Consider both direct and indirect costs• Identify most costly steps and focus
improvement efforts on them
Benchmarking
• Studying how other organizations perform the same business process
• Informal benchmarking– Check with customers– Pose as customers
• Formal benchmarking– Establish formal
relationship with other organization
3. (BPI) Developing To-Be System Concept
• A small amount of information gathering is needed
• To-Be system is still very similar to As-Is system
• But some (often very few) processes are completely reworked
BUSINESS PROCESS REENGINEERING (BPR)
Business Process Reengineering
• “Fundamental rethinking and radical redesign of business processes to achieve dramatic improvements…”
• Throw away everything• Start with a blank page• Appealing, but very expensive and risky
1. (BPR) Understanding the As-Is System
• Little effort spend here• Just get a basic understanding of the As-Is
system– It’s going to be scrapped anyway
2. (BPR) Identifying Improvement Opportunities
• Focus is on radical improvements– These are not easy to identify
• Need techniques that are more powerful than is BPA or BPI
• Need to be pushed to“think outside of the box”
Techniques for Identifying Improvements Opportunities
1. Outcome Analysis2. Breaking Assumptions3. Technology Analysis4. Activity Elimination5. Proxy Benchmarking6. Process Simplification
Outcome Analysis
• Consider desirable outcomes from customers’ perspective
• Pretend to be the customer• Consider what the organization could enable
the customer to do– Insurance company fixes cars
Breaking Assumptions
• Identify fundamental business rules• Systematically break each rule• Identify how the the business would benefit if
rule is broken– Bank accepts NSF checks & draws funds from
credit card
Technology Analysis
• Analysts & managers list important and interesting technologies
• The group identifies– How each can be applied to business– The benefits of each scenario • Saturn building intranet with suppliers for JIT parts delivery
Activity Elimination
• Identify what would happen if each organizational activity were eliminated
• Use “force-fit” to test all possibilities, even though some results might be silly– Mortgage company removes approval process
Proxy Benchmarking
• List different industries that have a similar structure
• Look for techniques from other industries that could be applied by the organization
• Throw in a few radically different industries– Hotel might look at:– Airlines, newspapers, rock concerts
Process Simplification
• Eliminate complexity from routine transactions• Concentrate separate processes on exception
handling– Online course registration– Handle lack of prerequisites separately
3. (BPR) Developing To-Be System Concept
• New system is radically different• Requires extensive information gathering
DEVELOPING AN ANALYSIS PLAN
Developing an Analysis Plan• Analysis Plan: plan for activities during the
analysis phase• Select analysis strategy first– Determined by project sponsor– It is a business decision• Potential business value• Project cost• Breadth of analysis• Risk
Analysis Strategies• Potential business value– BPA: benefits are tactical and small– BPI: potential benefits are moderate– BPR: largest potential benefits
Analysis Strategies• Project cost– BPA• Narrow scope, lest expensive
– BPI• Depending on scope, can be moderately expensive
– BPR• Almost always very expensive
Analysis Strategies• Breadth of analysis• The extent to which the analysis looks throughout
the entire business function and beyond– BPA• Very narrow focus on current systems only
– BPI• More extensive, but usually in just one narrow area
– BPR• Broad perspective, focusing on many business processes
Analysis Strategies• Risk – of failure due to:– Being unable to complete the system– The completed system being unable to deliver the
business benefits• BPA
– Low risk (same processes used)
• BPI– Low to Moderate
• BPR– High (completely new system)
Characteristics of Analysis Strategies
BPA BPI BPR
Potential Business Value
Low-Moderate Moderate High
Project Cost Low Low-Moderate High
Breadth of Analysis
Narrow Narrow-Moderate
Very Broad
Risk Low Low-Moderate Very High
Avoid Classic Analysis Mistakes
• Reduced analysis time– Solution?– Use RAD and timeboxing
• Requirement gold-plating– Unnecessary features are added– Users over-specification of features– Solution?– Expensive requirements should be re-verified with requester
Lower cost solutions should be looked at
Analysis Tasks
• How do we do the following?1. Understanding the As-Is system2. Identifying improvements3. Developing a concept for To-Be system
Analysis Tasks
• To accomplish these tasks:– Need to gather information
• Many projects go wrong– due to a poor understanding of the requirements
early on
1st challenge of Info Gathering
Finding the right people to participate
2nd challenge of Info Gathering
Deciding how to gather the informationFive techniques:
1. Interviews2. Joint Application Design (JAD)3. Questionnaires4. Document Analysis5. Observation
1. INTERVIEWS
Interviews
• Most commonly used technique• Very natural– If you need to know something, you ask someone
• There are 5 basic steps to interviewing…
Interviews -- Five Basic Steps
1. Selecting interviewees2. Designing interview questions3. Preparing for the interview4. Conducting the interview5. Post-interview follow-up
1. Selecting Interviewees
• Need an interview schedule– list all people to be interviewed– when each will be interviewed– for what purpose they will be interviewed
• The list may be informal… or it may be part of the Analysis Plan
• List is based on info. needed
1. Selecting Interviewees
• Good to get different perspectives– Managers– Users– Ideally, all key stakeholders
• Select people for political reasons• Interviewing is iterative– List often grows by 50% to 75 %
2. Designing Questions
• Don't ask for information that can be obtained elsewhere
• Want to show interviewee respect• Will get better information anyway
2. Designing QuestionsTypes of Questions Examples
Closed-Ended Questions * How many telephone orders are received per day?
* How do customers place orders?* What additional information would you like the new system to provide?
Open-Ended Questions * What do you think about the current system?* What are some of the problems you face on a daily basis?* How do you decide what types of marketing campaign to run?
Probing Questions * Why?* Can you give me an example?* Can you explain that in a bit more detail?
Closed-Ended Questions
• Requires a specific answer• Often multiple choice• Good for specific, precise info.– not "are there a lot of requests?"– but "how many requests are there?"
• Analyst is control• Doesn't uncover "why"
Open-Ended Questions
• Leave room for elaboration• Gives interviewee more control• Yields more rich, deep info
Probing Questions
• Follow-up questions• For clarification• Encouraged to expand answer• Show your listening and interested
2. Designing Questions
• No one type of question is best• Initially use unstructured interviews to
determine As-Is system (open-ended questions)
• As the analyst gains knowledge, structured interviews will be used (closed-ended questions)
2. Designing Questions
• Unstructured interview– Broad, roughly defined information
• Structured interview– More specific information
Interviewing Strategies
Howcan order
processing beimproved?
How can we reduce thenumber of times that customers
return ordered items?
How can we reduce the number oferrors in order processing (e.g., shipping
the wrong products)?
Top-down
Bottom-up
High-level:Very general
Medium-level:Moderately specific
Low-level:Very specific
3. Preparing for the Interview
• Prepare for the interview in the same way you would for a presentation
• Prepare general interview plan– List of question– Anticipated answers and follow-ups– Segues between related topics
• Confirm interviewee's area of knowledge– Don't ask questions that can't be answered
• Set priorities in case of time shortage
3. Preparing for the Interview
• Structured Interviews with closed-ended questions take longer
• Don't try to "wing it"
–will need follow-up interviews–user's don't like you to waste their time
4. Conducting the Interview• Appear professional and unbiased• Build rapport (and trust) with interviewee• Record all information• Check on organizational policy regarding tape recording• Be sure you understand all issues and terms• Separate facts from opinions• Give interviewee time to ask questions• Be sure to thank the interviewee• End on time
4. Conducting the InterviewPractical Tips
• Don’t worry, be happy• Pay attention• Summarize key points• Be succinct• Be honest• Watch body language
5. Post-Interview Follow-Up
• Prepare interview notes• Prepare interview report within 48 hours• Get buy-in from interviewee• Look for gaps and new questions
2. JOINT APPLICATION DESIGN (JAD)
JAD Key Ideas
• Allows project managers, users, and developers to work together
• May reduce scope creep by 50%• Avoids requirements being too specific or too
vague
Joint Application Design (JAD) Important Roles
• Facilitator• Scribe
Joint Application Design (JAD) Setting
• U-Shaped seating• Away from distractions• Whiteboard/flip chart• Prototyping tools• e-JAD
The JAD Session
• Include 10 to 20 users• Tend to last 5 to 10 days over a three week period• Prepare questions as with interviews• Formal agenda and groundrules• Facilitator activities– Stay neutral– Keep session on track– Help with technical terms and jargon– Record group input– Help resolve issues
• Post-session follow-up
3. QUESTIONNAIRES
Questionnaire Steps
• Selecting participants– Using samples of the population
• Designing the questionnaire– More important than interview questions– Prioritize questions to grab attention– Distinguish between• Fact-oriented questions (specific answers)• Opinion questions (agree – disagree scale)
– Test the questionnaire on colleagues
Questionnaire Steps• Administering the questionnaire– Need to get good response rate– Explain its importance & how it will be used– Give expected response date– Give it out in person– Follow up on late returns– Have supervisors follow up– Promise to report results
• Questionnaire follow-up– Send results to participants
4. Document Analysis
Document Analysis• Provides clues about the "formal" existing As-Is
system• Typical documents– Forms– Reports– Policy manuals
• Look for user additions to forms• Look for unused form elements• Do document analysis before interviews
5. Observation
Observation
• Users/managers often don’t remember everything they do
• Validates info gathered in other ways• Behaviors change when people are watched• Keep low profile, don’t change the process• Careful not to ignore periodic activities– Weekly … Monthly … Annual
Selecting the Appropriate Techniques