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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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Chapter 7 determining system requirements l.jpg

Analysis Phase

Chapter 7Determining System Requirements


Sdlc a nalysis phase l.jpg

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


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Objectives

  • 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)


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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


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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)


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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


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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


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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


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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


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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


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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”


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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


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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


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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

Scribe

Users

Managers

  • 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

Sponsor

  • 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


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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


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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


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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


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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


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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


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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


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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


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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 (Amazon.com)

  • 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)


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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

Requirement

determination


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