systems investigation and analysis c h a p t e r 12

SystemsInvestigationand Analysis

C H A P T E R

12

An Overview of Systems Development

Participants in Systems Development

StakeholdersIndividuals who ultimately benefit from the systems

development project

UsersIndividuals who interact with the system regularly

Participants in Systems Development

Systems analystA professional who specializes in analyzing and designing

business systems

ProgrammerThe individual responsible for modifying or developing

programs to satisfy user requirements

The Systems Analyst

[Figure 12.1]

Why Initiate a Systems Development Project?

[Figure 12.2]

Information Systems Planning

Translation of strategic and organizational goals into systems development initiatives

[Figure 12.3]

[Figure 12.4]

The Steps of IS Planning

Strategic planDevelop objectivesIdentify IS projectsSet prioritiesAnalyze resource

requirementsSet schedulesDevelop planning

document

Information Systems Planning

Developing a competitive advantage requires creative and critical analysis.Creative analysis

The investigation of new approaches to existing problems

Critical analysisUnbiased and careful questioning of whether system elements are

effective and efficient and whether new relationships should be established

Establishing Objectives for Systems Development

The impact a system has on an organization’s ability to meet its goals determines the true value of that system to the organization.

Mission critical systemsSystems that play a pivotal role in continued operation and

goal attainment

Establishing Objectives for Systems Development

Performance objectivesQuality or usefulness of the outputQuality or usefulness of the format of the outputSpeed at which output is generated

Cost objectivesDevelopment costsCosts related to the uniqueness of the system applicationFixed investments in hardware and related equipmentOngoing operating costs of the system

Systems Development Life Cycles

[Figure 12.6]

The Traditional Systems Development Life Cycle

Major problem: User does not see the solution until the system is nearly complete.

Changes to the SDLC

[Figure 12.5]

The Traditional Systems Development Life Cycle

Systems investigation Potential problems and opportunities are identified and

considered in light of the goals of the business.

Systems analysisExisting systems and work processes are studied and

strengths and opportunities for improvement are identified.

The Traditional Systems Development Life Cycle

Systems designResults in a technical design that either describes the new

system or describes how the existing system will be modified.

Systems implementationVarious system components are created (or acquired),

assembled, and placed into operation.

Systems maintenance and reviewThe system is maintained and modified so that it continues

to meet changing business needs.

Advantages & Disadvantages of Traditional SDLC

[Table 12.2]

Prototyping

An iterative approach to systems developmentOperational prototype

Accesses real data files, edits input data, makes necessary computations and comparisons, and produces real output

Non-operational prototypeA mockup, or model

An Iterative Approach to Systems Development

[Figure 12.7]

Prototyping

[Figure 12.8]

Advantages and Disadvantages of Prototyping

[Table 12.3]

Rapid Application Development (RAD)

A technique that employs tools, techniques, and methodologies designed to speed application development

Joint application developmentA process for data collection and requirements analysis

involving group meetings

Advantages and Disadvantages of RAD

[Table 12.4]

The End-User Systems Development Life Cycle

End-user systems developmentAny systems development project in which the primary

effort is undertaken by some combination of business managers and users

Software Capability Maturity Model

[Table 12.5]

Factors Affecting Systems Development Success

Factors Affecting Systems Development Success

Degree of changeQuality of project planningUse of project management toolsUse of formal quality assurance processesUse of CASE tools

Degree of Change

Can greatly affect the probability of a project’s success

[Figure 12.9]

Problems when Initiating New or Modified Systems

Fear that employee will lose his/ her job, power, or influence within the organization

Belief that the proposed system will create more work than it eliminates

Reluctance to work with “computer people”

Problems when Initiating New or Modified Systems

Anxiety that proposed system will negatively alter organization’s structure

Belief that other problems are more pressing, or that the system is being developed by people unfamiliar with “the way things need to get done”

Unwillingness to learn new procedures or approaches

Quality of Project Planning

The bigger the project, the more likely that poor planning will lead to significant problems.

RunawaysSystems development projects which are far over budget

and past delivery dates

Use of Project Management Tools

Project scheduleDetailed description of what is to be done

Project milestoneCritical date for the completion of a major part of the

project

Project deadlineDate that the entire project is to be completed and

operational

Use of Project Management Tools

Critical pathAll activities, that if delayed, would delay the entire

project

Program Evaluation and Review Technique (PERT)A formalized approach that involves creating three time

estimates for an activity: shortest possible time, most likely time, and longest possible time

Use of Project Management Tools

Gantt chartA graphical tool used for

planning, monitoring, and coordinating projects

Essentially a grid that lists activities and deadlines

[Figure 12.10]

Use of Formal Quality Assurance Processes

The development of information systems requires constant trade-offs of schedule and cost versus quality.

Many IS organizations have incorporated ISO 9000, total quality management, and statistical process control principles into the way they produce software.

Use of CASE Tools

Computer-aided software engineering (CASE) Technology that

automates tasks required in a systems development effort and enforces adherence to the SDLC

Upper-CASE tools Provide automated

assistance with systems investigations, analysis, and design activities

Use of CASE Tools

Lower-CASE tools Focus on the later implementation stage of systems

developmentCan automatically generate structured program code

Integrated-CASE (I-CASE) toolsProvide links between upper- and lower-CASE

packages

Advantages and Disadvantages of CASE Tools

[Table 12.9]

Systems Investigation

Initiating Systems Investigation

Systems request formA document that is filled out by someone who wants the

IS department to initiate systems investigationIncludes:

Problems in or opportunities for the systemObjectives of systems investigationOverview of the proposed systemExpected costs and benefits

Participants in Systems Investigation

[Figure 12.11]

Feasibility Analysis

A step in systems investigation that assesses technical, economic, operational and schedule feasibility

[Table 12.10]

Feasibility Analysis

Net present valuePreferred approach for ranking competing projects and

determining economic feasibilityRepresents the net amount by which project savings

exceed project expenses, after allowing for the cost of capital and the passage of time

The Systems Investigation Report

Summarizes results of the systems investigation and feasibility analysis

Recommends a course of action Reviewed by a steering

committee: senior management and users from IS department and other functional areas

[Figure 12.12]

Systems Analysis

General Analysis Considerations

Assembling the participants for systems analysisCollecting appropriate data requirementsAnalyzing the data and requirementsPreparing a report on the existing system, new

system requirements, and project priorities

Participants in Systems Analysis

Members of the original development teamUsersStakeholdersIS personnelManagement

Data Collection

Identify sources of data (internal and external)Perform data collection

Structured interviewsUnstructured interviewsDirect observationQuestionnairesStatistical sampling

Data Analysis

Manipulating the collected data into usable formData modeling

Uses entity-relationship diagrams (ER)

Activity modelingUses data-flow diagrams (DFD)

Application flowchartsCharts that show the relationships among applications or

systems

Data Analysis

Grid chartsA table that shows the relationship among various

applications

[Figure 12.17]

Data Analysis

CASE toolsMany systems development projects use upper-CASE

tools to complete analysis tasks.

CASE repository A database of system descriptions, parameters and

objectives

Requirements Analysis

A method to determine user, stakeholder, and organizational needs

Asking directlyCritical success factorsThe IS plan

[Figure 12.18]

continued...

Requirements Analysis

Screen and report layoutScreen layout

Allows designer to quickly and efficiently design features, layout, and format of a display screen

Report layoutAllows designers to diagram and format printed reports

Requirements analysis tools

Elements of theSystems Analysis Report

Strengths and weaknesses of the existing system from a stakeholder’s perspective

User/stakeholder requirements for the new system (also called functional requirements)

[Figure 12.20]

Organizational requirements for the new system

A description of what the new information system should do to solve the problem

Elements of theSystems Analysis Report