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Information Systems Lifecycle Introduction to Feasibility Studies Monica Farrow EM G30 monica@macs.hw.ac.uk Material available on Vision. F28SD2 Software Design. Timetable. Thu Mar 5 G44 Tue Mar 10 NS136 Thu Mar 12 – No lecture – work independently

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F28sd2 software design

Information Systems Lifecycle

Introduction to Feasibility Studies

Monica Farrow

EM G30 monica@macs.hw.ac.uk

Material available on Vision

F28SD2 Software Design


F28SD Software Design


Thu Mar 5 G44

Tue Mar 10 NS136

Thu Mar 12 – No lecture – work independently

Tue Mar 17 – guest visitor starting at 11:15 (?)

Lyle Barbour from SOPRA group

Maybe lasting up to 1hr 30 mins

Location to be arranged

Thu Mar 19 G44

Tue Mar 24 NS136 back with CS

Process models
Process models

  • There are various types of software lifecycle models

    • Waterfall, spiral, agile...

Waterfall process model

F28SD Software Design

Waterfall process model

Requirements capture

System and

software design

Implementation and unit testing

Integration and system testing

You’ll find slightly different

versions elsewhere.

Operation and maintenance

Boehm s spiral model

F28SD Software Design

Boehm’s spiral model

Scrum an agile process
SCRUM – an agile process

Other diagrams show 2-4 weeks

Rather than 30 days

Information systems lifecycle

F28SD Software Design

Information Systems lifecycle

  • Software lifecycle models

    • concentrate on design and implementation of a software system

    • models lack an overall picture of the organisation and its business processes

  • A traditional structured design method extended in this manner is shown next

    (Based on Avison and Shah)

  • The similarities are clear

  • So are the new features

F28sd2 software design

F28SD Software Design

Problems with

existing system

New business


Information Systems lifecycleAfter Avison and Shah p71








study report












and tools



data flow







New system

data flow



Training and

test plans





New system

in operation






New problem


What s similar

F28SD Software Design

What’s similar?

Stages rather like waterfall

Repeats with review like spiral

Progress in terms of artefacts

What s added

F28SD Software Design

What’s added?

Feasibility study

Review during maintenance

System is an open one

Operation feeds back to design

Review during maintenance

F28SD Software Design

Review during maintenance

Learning from experience

Effectiveness of the solution

Correctness of function


Suitability for the business process

Effectiveness of the process

Kept to time?

Kept to budget?

Lessons learned for future developments

System is an open one

F28SD Software Design

System is an open one

Take account of influences from the organisation which change over time

Managerial directives

often arbitrary

but often dominate decision making

New opportunities

business process change requires system change

Longer term information systems planning

system change to maintain business process

Operation feeds back to design

F28SD Software Design

Operation feeds back to design

Operation reveals errors - “maintenance” in SE

Operation reveals bottlenecks for the business

Operation reveals new opportunities for business

Operation reveals difficulties for users

Summary : from the original ‘build a system then hand it over’ approach, we must be now more aware of the user and their environment.

Feasibility study

F28SD Software Design

Feasibility study

  • Propose and evaluate alternatives

  • Establish priorities

  • Gather information

  • Perform cost-benefit analysis

  • Form options for computerisation

  • Present conclusions

    The negative option is a valid option!

Objectives of feasibility study
Objectives of feasibility study

  • A feasibility study should provide management with enough information to decide:

    • whether the project can be done

    • whether the final product will benefit its intended users

    • what are the alternatives among which a solution will be chosen (during subsequent phases)

    • is there a preferred alternative

  • After a feasibility study, management makes a go/no go decision

  • The feasibility study is a management-oriented activity

Inputs and outputs
Inputs and outputs
















Feasibility study







Terms of reference
Terms of reference

  • Project objectives

  • System boundary

  • Responsibility

  • Constraints

  • Reporting mechanism

Terms of reference1
Terms of reference

  • Project objectives

    • Unambiguous statement of what the client expects

    • Must be agreed before further work is done

  • System boundary

    • The scope of the feasibility study

    • What should be considered

    • What should not be considered

Terms of reference continued
Terms of reference continued

  • Responsibility

    • Who will supervise the project?

    • Who can authorise changes during the study?

    • Is the scope fixed?

  • Constraints

    • Budget

    • Time scales

    • Resources

    • Etc

  • Reporting

    • How will the report be expected?

    • To whom will the report be presented?

    • Who else can see the report?

Tasks in conducting the study
Tasks in conducting the study

  • Study current situation

  • Analyse requirements

  • Consider alternatives

  • Analyse economic/financial situation

Current situation
Current situation

  • Study current situation

    • The present organizational system, including users, policies, functions, objectives,...

    • Problems with the present system (inconsistencies, inadequacies in functionality, performance,...,

    • Gain thorough understanding

    • Establish reality of problems

    • Look for opportunities

    • Establish cause and effect

Pieces framework
PIECES framework

  • The PIECES framework can help in identifying problems to be solved, and their urgency:

    • Performance -- Does current mode of operation provide adequate throughput and response time?

    • Information -- Does current mode provide end users and managers with timely, pertinent, accurate and usefully formatted information?

    • Economy -- Does current mode of operation provide cost-effective information services to the business? Could there be a reduction in costs and/or an increase in benefits?

Pieces framework1
PIECES framework

  • Control -- Does current mode of operation offer effective controls to protect against fraud and to guarantee accuracy and security of data and information?

  • Efficiency -- Does current mode of operation make maximum use of available resources, including people, time, flow of forms,...?

  • Services -- Does current mode of operation provide reliable service? Is it flexible and expandable?

Analyse requirements
Analyse requirements

  • Analyse requirements (What not how)

    • Objectives and other requirements for the new system

      • what needs to change?

      • What would the stakeholders like to achieve?

    • Constraints, including non-functional requirements on the system (preliminary pass)

    • What is the client’s intention?

    • What capabilities are needed?

    • Data input and stored

    • Information output

Tasks in conducting the study continued
Tasks in conducting the study continued

  • Consider alternative solutions

    • Possible alternatives (the current system is always one of those)

      • Different business processes for solving the problems

      • Different levels/types of computerization for the solutions

    • Advantages and disadvantages of the alternatives

  • Economic/financial analysis

    • Costs of alternatives

    • Opportunity costs of inaction

    • Benefits of changes

    • Impact on business as a whole

Four tests for feasibility
Four tests for feasibility

  • There are four categories of feasibility tests

    • Operational feasibility

      • How well will solution work in organisation? How do people feel about it?

    • Technical feasibility

      • Practical? Expertise?

    • Schedule feasibility

      • Reasonable timetable?

    • Economic feasibility

      • Cost-effective?

Operational feasibility acceptability
Operational Feasibility: Acceptability

  • How do end-users and managers feel about the problem (solution)?

  • It's not only important to evaluate whether a system can work but also evaluate whether a system will work.

  • A workable solution might fail because of end-user or management resistance.

    • Does management support the project?

    • How do the end-users feel about their role in the new system?

    • What end-users or managers may resist or not use the system? People tend to resist change. Can this problem be overcome? If so, how?

    • How will the working environment of the end-users change?

Operational feasibility acceptability1
Operational Feasibility: Acceptability

  • Can or will end-users and management adapt to the change?

    • Internal issues, such as manpower problems, labour objections, manager resistance, organizational conflicts and policies;

    • also external issues, including social acceptability, legal aspects and government regulations.

  • The PIECES framework can also be used for each alternative solution

    • Performance, Information, Economy, Control, Efficiency, Services

  • Technical feasibility
    Technical feasibility

    • Is the proposed technology or solution practical?

      • Do we currently possess the necessary technology?

      • Do we possess the necessary technical expertise, and

        • Is the schedule reasonable for the team?

      • Is relevant technology mature enough to be easily applied to our problem?

      • Is it compatible with our other systems?

    Technical feasibility1
    Technical feasibility

    • Some firms like to use state-of-the-art technology, but most firms prefer to use mature and proven technology.

      • A mature technology has a larger customer base for obtaining advice concerning problems and improvements.

    • Assuming that required technology is practical, is it available ‘in-house’?

      • If so, does it have the capacity to handle the solution.

      • If not, can it be acquired?

      • Is it available within given resource constraints (i.e., budget, schedule,...)?

    Schedule feasibility
    Schedule feasibility

    • Do we have the skills required to properly apply that technology;

      • True, all information systems professionals can learn new technologies;

      • However, that learning curve will impact the technical feasibility of the project;

      • Specifically, it will impact the schedule.

    • Given our technical expertise, are the project deadlines reasonable?

      • Some projects are initiated with specific deadlines;

      • You need to determine whether the deadlines are mandatory or desirable. What are the consequences of delay?

      • If the deadlines are desirable rather than mandatory, the analyst can propose alternative schedules.

      • Missed schedules are bad, but inadequate systems are worse!

    Economic feasibility
    Economic feasibility

    • The bottom line in many projects is economic feasibility.

    • During the early phases of the project, economic feasibility analysis amounts to little more than judging whether the possible benefits of solving the problem are worthwhile.

    • As soon as specific requirements and solutions have been identified, the analyst can weigh the costs and benefits of each alternative.

    • This is called a cost-benefit analysis.

    Cost benefit analysis
    Cost/benefit analysis

    • The purpose of a cost/benefit analysis is to answer questions such as:

      • Is the project justified (because benefits outweigh costs)?

      • Can the project be done, within given cost constraints?

      • What is the minimal cost to attain a certain system?

      • What is the preferred alternative, among candidate solutions?

    Cost benefit analysis1
    Cost/benefit analysis

    • Examples of things to consider:

      • Hardware/software selection

      • How to convince management to develop the new system

      • Selection among alternative financing arrangements (rent/lease/purchase)

    • Difficulties

      • Discovering and assessing benefits and costs. They can both be intangible, hidden and/or hard to estimate,

      • It's also hard to rank multi-criteria alternatives

    Types of benefit
    Types of benefit

    • Examples of particular benefits:

      • cost reductions,

      • error reductions,

      • increased throughput,

      • increased flexibility of operation,

      • Improved operation,

      • better (e.g., more accurate) and more timely information

    Types of benefit1
    Types of benefit

    • Benefits may be classified into one of the following categories:

      • Monetary -- when $-values can be calculated

      • Tangible (Quantified) -- when benefits can be quantified, but $-values can't be calculated

      • Intangible -- when neither of the above applies

    • How to identify benefits?

      • By organizational level (operational,lower/middle/higher management)

      • or by department (production,purchasing, sales,...)

    Types of cost
    Types of cost

    • Project-related costs

      • Development and purchasing costs:

        • who builds the system(internally or contracted out)?

        • software used (buy or build)?

        • hardware (what to buy, buy/lease)?

        • facilities (site, communications, power,...)

      • Installation and conversion cost

        • installing the system,

        • training of personnel,

        • file conversion,....

    Types of cost1
    Types of cost

    • Operational costs (on-going)

      • Maintenance

        • hardware (maintenance, lease, materials,...),

        • software (maintenance fees and contracts), facilities

      • Personnel: operation, maintenance

    Types of cost2
    Types of cost

    • For a small business that wants to introduce a PC-based information system, these cost categories translate to the following:

      • Project costs

        • purchasing (hardware, software, office furniture),

        • customizing software, training,

        • system installation

        • and file conversion

      • On-going costs:

        • operating the system (data entry, backups, helping users, vendors etc.),

        • maintenance (software) and user support,

        • hardware and software maintenance,

        • supplies

    F28sd2 software design

    • More on costs next time

    • Most of these notes come from Ch9 of Systems Analysis and Design Methods b Whitten, Bentley and Dittman

    • You can read this chapter in full electronically, on Vision