Chapter 11 Presentation Systems Implementation, Operation, and Control Computer System

Presentation Outline I.The Steps of Systems Implementation II.Planning and Organizing a Systems Project III.Control Over Nonfinancial Information System Resources

I. The Steps of Systems Implementation A. Establish Plans and Controls 1. Gantt Charts 2. Simple Network Diagram B. Executing Planned Implementation Activities C. Follow up and Evaluate the New System

A. Establish Plans and Controls Plans should incorporate three major components: 1. Breakdown of the project into various phases. 2. Preparing specific budgets applicable to each phase 3. Setting up specific time tables applicable to each phase.

A1. Gantt Charts Gantt charts show actual and planned time for activities. However, they do not show the relationship between various plan activities. Evaluate software Select software Select computer Train employees Test system Planned Time Actual Time Month

A2. Simple Network Diagram A network diagram depicts the order in which activities must be performed. Contact Vendors Review Budget Evaluate Software Allocate Funds Select Software Train Employees Contact Vendors Select Computer Implement Computer Complete Start

A3. Program Evaluation and Review Technique (PERT)  The network diagram can be expanded to to include estimated times for each of the individual activities for the project.  PERT (also known as Critical Path Method) is used to estimate the critical path for a project.  The critical path is a list of activities that are critical to the project in the sense that if any one of them is delayed, the entire project will be delayed.

B. Executing Planned Implementation Activities 1.Employee Training 2.Acquiring and Installing New Computer Equipment 3.Detailed Systems Design 4.Writing and Testing Computer Programs 5.System Testing 6.Standards Development 7.Documentation 8.File Conversion

1. Employee Training  It is likely that if employees are not adequately trained, they will simply ignore the system.  Management must often decide whether to retrain existing employees or hire new personnel. See retraining existing employees considerations on p. 396

2. Acquiring and Installing New Computer Equipment Facility considerations include:  Humidity and temperature controls  False floors for wiring Security measure considerations include:  Special fire extinguishing  Video monitoring systems  Specialized door locks

3. Detailed Systems Design  The design specifications for a computer program are determined by the design team, not the programmer.  Although the programmer’s primary function is to implement a specific plan, it is important for the programmer to work in conjunction with the design team.

4. Writing and Testing Computer Programs  Programmers write programs in accordance with design specifications.  Smaller installations may use prepackaged computer programs.  Testing should involve trying to do everything possible to find something wrong with the program.

5. System Testing  Direct Approach – switching to the new system and abandoning the old system at a fixed point in time (cutover point).  Parallel Operation – run all transactions on both old and new systems simultaneously, and compare results. Safe but expensive.  Modular conversion – phasing in a new system in segments. Can significantly extend testing period.

6. Standards Development  The computer system should follow certain standards to ensure proper functioning and compatibility.  It is important that the individual modules of a system interface properly with other system components.

7. Documentation  Training new employees  Providing programmers and analysts with useful information for future program evaluation and modification activities.  Providing auditors with useful information for evaluating internal controls.  Assisting in assuring that system design specifications are met. Documentation serves many purposes including:

8. File Conversion  In many cases, files maintained manually must be converted to computer format.  Conversion from manual to computer formats can result in numerous errors. Therefore, much of the data must be screened after it is entered.

C. Evaluating the New System Follow-up is necessary to ensure that the system is functioning as planned. Approaches to follow-up and evaluation include: Observation Questionnaires Performance Measures Benchmarks

II. Planning and Organizing a Systems Project A.Project Selection B.The Project Team C.Factoring a Project into Phases and Tasks D.Time Estimates E.Project Accounting

A. Project Selection  When resources are limited, funding should be allocated to projects yielding the greatest benefit to the organization.  The selection of projects by the steering committee helps to ensure user participation.

B. The Project Team  An application project team includes both technical people and users.  The leader may be from either group depending on the situation.  Project leader has direct responsibility to the steering committee for progress and completion. Also, maintains communication with principal user department manager.

C. Factoring a Project into Phases and Tasks The objective of project breakdown is to facilitate assignment and control of labor and other project resources. New System AnalysisImplementDesign ReportInterviewArchitect.DetailTrainInstall

D. Time Estimates  Guesstimates often work well at the beginning of a project since there is so much uncertainty.  Work measurement can be used to refine time estimates (See Fig on p. 402)  Estimates should be revised frequently since they can be improved as the project progresses toward to area to be completed.

E. Project Accounting A project accounting system is a cost accounting system in which costs are assigned to individual projects as the projects proceed through their development. (See Figure 11.9 on page 405)

III. Control Over Nonfinancial Information System Resources A.Nonfinancial Performance Measures B.Auditing the Information System C.Maintaining and Modifying the System

A. Nonfinancial Performance Measures 1.Hardware Performance 2.Software Performance 3.Personnel Performance

1. Hardware Performance  Measures of system utilization often include ratios such as CPU time actually used to that available. Utilization statistics can helpful in scheduling work and identifying a need for expansion.  Downtime is the percentage of the time that all or part of the network is unavailable for use.  The mean time between failures.  The mean time to repair the system. What are some measures of hardware performance?

2. Software Performance A very sound overall approach to evaluating software performance is to survey system users asking a large number of questions regarding:  Ease of use  Functionality  User friendliness Software performance must be constantly monitored because of environmental changes that could affect user satisfaction.

3. Personnel Performance  Evaluation of the quality of documentation written by programmers.  Data entry evaluation such as keystrokes per hour or records entered per hour.  Effectiveness of systems operators in running prescheduled jobs on time.  Efficiency of repairpersons in terms of number of repairs jobs and average length of time required for each repair.

B. Auditing the Information System  Obtain a detailed description of the internal control system. Internal control questionnaires are often used for this purpose.  Perform tests of compliance  Perform tests of transactions as they flow through the system. Extent of testing depends on the level to which controls exist and are in effective operation. Better controls could mean less transaction testing.

C. Maintaining and Modifying the System  All modifications to the systems software and data schema should be formally reviewed and approved.  Programmers should not have access to the operational copy of software being modified.  Programmers should only modify a non-operational copy of the original software. Once completed, the modified software should be carefully reviewed and then installed by an independent person.  All modifications should be carefully documented.

Summary  The Steps of Systems Implementation  Establish Plans and Controls  Execute Activities  Follow Up and Evaluate New System  Planning and Organizing a Systems Project  Selection of Projects  Organization of Project Team  Breakdown of Project Tasks  Project Accounting  Control Over Nonfinancial Information System Resources  Performance measures for hardware, software, and personnel  Auditing the Information System  Maintaining and Modifying the System