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Analysis Phase. Chapter 7 Determining System Requirements. SDLC: A nalysis phase. Input: Accepted project with baseline project plan and Work of statement Output: System requirement & best alternatives to design the system Output of phase 3 = Input of phase 4 Purpose:

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sdlc a nalysis phase
SDLC: Analysis phase
  • Input:
    • Accepted projectwith baseline project plan and Work of statement
  • Output:
    • System requirement & best alternatives to design the system
      • Output of phase 3 = Input of phase 4
  • Purpose:
    • How to determine requirements for the potential system?
    • How to structure the generated requirement?
    • How to select the best alternative design strategy?
  • Process:
    • Requirement determination
    • Requirement structuring
  • Participants & roles
    • Team of system analysts + end users
  • Describe traditional & modern methods to determine system requirements (SR)
  • Describe guideline for conducting interviews & to design questionnaire during requirement determination
  • Explain the advantages of observing workers and analysing existing business documents to determine SR
  • Describe modern method support requirement determination (JAD, prototyping)
  • Point out to rradical methods for requirement determination (BPR)
analysis of current organisation
Analysis of current organisation

Data needed to support job

(definition, volume, size)

Information needed

by people

People involved

Rules that govern how data

are handled and processed

Activities, steps

& sequence

of activities

Key events affecting

data value

When, how & by whom

data are moved, transformed

& stored

Objectives that

drives what & how

work is done

Business process

d etermining s ystem r equirements methods
Determining System Requirements Methods
  • Traditional methods :
    • Interviews
    • Survey via questionnaires
    • Direct observation of working people
    • Study business documents
  • Modern methods
    • Joint Application Design
    • Group Support System (GDSS)
    • Case tools
    • Prototyping
  • Radical methods
    • Business Process Reengineering (BPR)
traditional methods interviews
Traditional methods :Interviews
  • Open-ended question
    • is suitable to probe information which you cannot anticipate (in advance) all responses
      • E.g. Impact of Euro on (Gulf Countries)
  • Close-open question
    • Provide a range of answers from which the interviewee may choose
      • E.g. business intelligence practices
traditional methods guideline for interview
Traditional methods :Guideline for interview
  • Think careful about the subject you want to investigate
  • Set appointment
  • Prepare questions
  • Plan time for questions (check if you have enough time to complete the interview)
  • With either open or closed questions, do not phrase a question in a way that implies a right or wrong answer
  • Refer to the book for more information
  • Listen carefully to your interviewee to what he is being said
  • Thanks your interviewee and translate the interview in written document within 48 hours
  • Be careful during the interview and not set expectation about the new system or replacement system unless you are sure these features will be part of the delivery system
  • Identify variety of perspectives from the interview
traditional methods group interviews
Traditional methods :Group interviews
  • Catch up important people is frustrating (e.g. high managers)
  • Group interview overcome the problem of performing several separate interviews
  • Group interview is very hard to schedule
  • Group interview may be supported by technologies
traditional methods questionnaire
Traditional methods :Questionnaire
  • It includes
    • Structured questions
    • More questions than in interviews
    • Open and closed questions
  • Advantages
    • Let people to recall information
    • Is less time consuming: less time to complete than do interview
    • Allow to gather more information from different people in a short time and simultaneously
    • Is less biased during interpretation
    • Filled in at the convenience of the interviewee since it has to be returned by specific date
  • Disadvantages
    • No sense & feeling of persons
    • Not always possible to evaluate accuracy of answers, e.g. questionnaire filled in by other person than the expected one (secretary)
    • Less rich than interview
traditional methods guideline for questionnaires
Traditional methods :Guideline for questionnaires
  • Skills may be enhanced through experience
  • Questions must be clear in meaning & logical in sequence
  • Avoid ambiguity
  • Use short sentences
  • Make pre-test before reel use to check its relevance and usefulness
  • Use interviews first and questionnaire later for complex system in large organisation
  • Use questionnaire in small system and organisation
traditional methods direct observation of users
Traditional methods :Direct observation of users
  • It consists to observe people in their daily work to gather requirements instead of interviewing
  • Interviews and interviews have disadvantages: the first one don’t let people to answer and the second don’t let to recall
  • The memory (short & long term) is lacking efficiency
  • People are unable to answer some question, e.g. “how to interpret strategic information picked up from daily newspapers”
traditional methods analysis of existing documents
Traditional methods :Analysis of existing documents
  • Gather formal & informal system
    • Formal system is the official way a system works as described in organisational document, e.g. how to process complain of customer
    • Informal system # formal system; e.g. collecting strategic information
    • Gather information about current & future system (reports written by internal departments)
    • Analyse strategies & objectives of the organisation
  • Example of documents to be analysed when generating further requirements
    • Minutes of meeting
    • Annual reports
    • Business missions and strategy
    • Job description
    • Consultant reports
    • Training manuals
    • Flow chart & description of existing systems
    • Interviews of upper managers in newspapers
modern methods jad
Modern methods:JAD
  • Collect system requirement simultaneouslyfrom key people & reviewingsystem design
  • Bring a structure to the requirement determination phase of analysis & to the review that occur as part of design
  • Reduce time required for analysis collected requirements
  • Sharing different views of involved people affected by the system
  • Better manage organisational resources through bringing several roles in JAD sessions
roles involved in jad
Roles involved in JAD
  • Write detailed minute of meeting
  • Use laptop
  • Enter data to case tool
  • Give organisational directions
  • Explain motivations for system
  • Explain organisation impact of system
  • Emphasis support for requirement determination
  • Emphasis collaboration during SR
  • Explain their need
  • How they will use the system




  • Is a neutral person
  • Plan meetings
  • Set agenda
  • Facilitate discussions
  • Check completeness of the agenda
  • Don’t contribute to idea generation & opinions
  • Resolve conflicts & disagreements
  • Solicit all ideas

JAD leader

IT staff

System analyst


  • Learn from discussion
  • Propose idea
  • Evaluate technical feasibility
  • Explain limitation of current system
  • Limit their participation
  • Learn from end-users & managers
  • Don’t run the sessions
  • Don’t dominate the meeting
  • Fund the project
  • Attend beginning and end
  • Of meetings
procedure of jad
Procedure of JAD
  • JAD sessions are held in special room “U” equipped with
  • JAD last from 1/2 day to one week and may consist of several sessions
  • Output is a document that contains the finding of the JAD (agreed requirements)
  • JAD could be supported by case tools such planning tools and diagramming tools
  • JAD could also be supported by Group Support System
  • But most traditional JAD rely on computer for the scribe
  • JAD suffers from problem that are similar to group meeting
problems of group meeting
Problems of group meeting
  • Group meeting don’t allow all participant to speak
  • Outcomes (output) reflect views of only those who participate
  • Suffer from the dominance of the leader, i.e. outcome is influenced by the leader
  • Some persons are afraid to speak out for fear they will be criticised
  • Most people are not willing to criticise or challenge their boss
how can group support system gss overcome previous problems
How can group Support System (GSS) overcome previous problems
  • Advantages of GSS
    • GSS allow writing into computer rather than speaking
    • Guarantee of anonymity: comments typed into a GSS are anonymous
    • GSS is set up so that all members of the group can see what every member has been typing without showing the name “no one knows who typed what”
  • Consequences of GSS on group solving problems
    • Contribution of all participants during the JAD
    • Less dominance of leaders during discussion
    • Comments will be criticised but not the person himself
    • Important ideas are less likely to be missed
    • Poor ideas are more likely to be criticised
  • Disadvantages of GSS
    • Difficulties to solving conflict
modern methods prototyping
Modern methods:Prototyping
  • Used to improve the JAD
  • Is a form of Rapid Application Design (RAD)
  • Serves as the working description of needs (requirements) instead of document
  • Could also replace traditional SDLC or enhance it
  • Allows to quickly convert basic requirements into a working system through limited functions
prototyping is suitable for requirement determination when
Prototyping is suitable for requirement determination when
  • User requirements are not clear or well understood,
    • E.g. the case of new system that support decision system
  • One or few users and other stakeholders, involved with the system, have different visions
    • E.g. different distribution of information power
  • Possible design are complex and require concrete form to fully evaluate the system
    • E.g.designing a Strategic Business Intelligence System
  • Communication problems have existed in the past between users
    • E.g. Designing a system by a cross functional team
three disadvantages of prototyping
Three disadvantages of prototyping
  • Trend to avoid writing a formal documentation of system requirements which make the system more difficult to develop
  • Prototyping can become very idiosyncratic to the initial users and difficult to diffuse or adapt to other potential users
  • Prototype are often built as stand-alone systems, thus ignoring issues of sharing data and interactions with other existing systems
radical method business process re engineering bpr
Radical method Business Process Re-engineering (BPR)
  • Why BPR?
    • Previous traditional and modern methods for system requirements are used to automate existing business processesby new systems,
    • Changing conditions such as pressure of competition, globalisation, rapid change of customers’ needs have lead to re-engineer existing processes
    • Reengineering is driven by improvement in speed, quality &customer satisfaction
  • Definition of BPR
    • It refers to the search for, and implementation of radical change in business processes to achieve breakthroughimprovements in product and service
    • BPR is looking for new ways to perform current tasks
bpr and it
BPR and IT
  • How to perform BPR?
    • E.g. of question: “if we were a new organisation, how would we accomplish this activity?”
    • Changing the way work is done (now) implies to change the way information is shared, stored & processed
    • New ways may be radically different from how things are done now
    • E.g. selling books on the web (
  • Consequence of BPR
    • Radical increase in the quality of business processes can be achieved though creative application of IT
    • This is the purpose of System development Life Cycle (SDLC)
output deliverable requirement determination
Output/deliverable requirement determination
  • Input
  • Interviews, questionnaire, JAD sessions, direct observations of working people
    • study business documents, Group Support System (GDSS), and BPR
  • Output
    • Rough (raw) data gathered