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