Accounting Information System Romney Ch18

8/11/2019 Accounting Information System Romney Ch18

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2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 1 of 153

C HAPTER 18

Introduction to Systems

Development and Systems

Analysis


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INTRODUCTION

Questions to be addressed in this chapterinclude:

What are the phases in the systems developmentlife cycle?

Who are the individuals involved in systemsdevelopment?

What techniques are used to plan the developmentof a system?

How do you determine whether a particular systemis feasible?

How do people respond to systems changes, andhow can dysfunctional behavior be minimized?


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INTRODUCTION

As the environment, technology, and

competition change, an information

system must continually undergo changes.

These changes range from minor

adjustments to major overhauls.

Occasionally, the old system is scrapped

and replaced.


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INTRODUCTION

Companies change their systems for a variety ofreasons: To respond to changes in user needs or business needs.

To take advantage of or respond to technology changes.

To accommodate improvements in their business process.

To gain a competitive advantage and/or lower costs. To increase productivity.

To accommodate growth.

To accommodate downsizing or distribute decision making

To integrate incompatible systems.

To replace a system that is aged and unstable.


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INTRODUCTION

Developing quality, error-free software is difficult,expensive, and time-consuming.

Projects tend to deliver less than expected and consumemore time and money.

A KPMG survey found that 35% of all major informationsystems projects were classified as runawayshopelessly incomplete and over budget. Major cause of runaways: Skimping on systems development

processes.

Omitting basic systems development steps becomestempting but may lead to disaster as developers createwell-structured systems that fail to meet user needs orsolve business problems.


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INTRODUCTION

This chapter discusses five topics:

Systems development life cycle

Planning activities during the systems

development life cycle Feasibility analysis

Behavioral aspects of change

Systems analysis


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SYSTEMS DEVELOPMENT LIFE CYCLE

Whether systems changes are major orminor, most companies go through asystems development life cycle.

In this section, we discuss the steps in thecycle and the people involved.




The five stages in the systemsdevelopment life cycle are:

Systems analysis

Conceptual design Physical design

Implementation and conversion

Operation and maintenance





Systems analysis







As organizations grow and change, they mayneed more or better information.

Systems analysis is the first step. It includes:

Initial investigation Involves gathering the information needed

to buy or develop a new system and

determining whether it is a priority.






Initial investigation Systems survey

If the system is a priority, survey the

existing system to define the nature and

scope of the project and identify the

strengths and weaknesses of the system.







Feasibility study

Involves an in-depth study of the proposed

system to determine whether its feasible.







Feasibility study

Determination of information needs and systemrequirements

Involves finding out and documenting what

users and management need.

This is the most important aspect of

systems analysis.







Feasibility study

Determination of information needs and systemrequirements

Delivery of systems requirements

Involves preparation of a report

summarizing the systems analysis work.

This report is submitted to the information

systems steering committee.





Systems analysis







In the conceptual design phase, the companydecides how to meet user needs.

Tasks in this phase include:

Identify and evaluate design alternatives Possibilities include:

Buying software

Developing in-house

Outsourcing






Identify and evaluate design alternatives Develop design specifications

Involves writing up details of what the system is to

accomplish and how it is to be controlled and

developed.






Identify and evaluate design alternatives Develop design specifications

Deliver conceptual design requirements

These requirements will be forwarded to the

information systems steering committee.





Systems analysis







In the physical design phase, the broad, user-oriented requirements of the conceptual designare translated into detailed specifications thatcan be used by programmers to code theprograms.

Tasks include:

Design outputs, database, and inputs

Develop programs

Develop procedures

Design controls

Deliver developed system Goes to information systems steering committee





Systems analysis







This is the capstone phase during which everythingcomes together.

Tasks include: Develop an implementation and conversion plan.

Needed because of the complexity and importance of this phase. Install any new hardware and software.

Train personnel.

New employees may need to be hired and trained or existingemployees relocated.

Test the system and make any needed modifications. Complete the documentation.

Convert from the old to the new system.

Deliver operational system.

Send the final report to the IS steering committee.





Systems analysis







Once the system is up and running, operationsand monitoring continue.

Tasks include:

Fine-tune and do post-implementation review. Operate the system.

Periodically, review and modify the system.

Do ongoing maintenance.

Deliver improved system.


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Eventually, a major modification or systemreplacement is necessary, and the systemsdevelopment life cycle (SDLC) will start over.

In addition to the preceding five phases, three

activities are performed throughout the life cycle: Planning.

Managing behavioral reactions to change.

Assessing ongoing feasibility.

These three activities will be discussed in thischapter.

Additionally, the first phase in the SDLC, systemsanalysis, will be discussed in more detail.


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THE PLAYERS

Many people are involved in developing andsuccessfully implementing an AIS, including:

Top management

Accountants The information systems steering committee

The project development team

Systems analysts

Computer programmers External players


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THE PLAYERS

Many people are involved in developing andsuccessfully implement an AIS, including:

Top management



Systems analysts



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THE PLAYERS

Top managements role in systems developmentis to: Provide support and encouragement a clear signal

that user involvement is important.

Help align the systems with corporate strategies.

Establish system goals and objectives.

Review IS department performance and leadership.

Establish policies for project selection and

organizational structure. Participate in important systems decisions.


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THE PLAYERS

User management needs to: Determine information requirements for departmental

projects.

Assist systems analysts with project cost-benefit

estimates. Assign key staff members to development projects.

Allocate funds.


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THE PLAYERS


Top management



Systems analysts



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THE PLAYERS

Accountants also play an important role insystems development: As AIS users, they must determine their information needs

and systems requirements and communicate them to

system developers. As members of project development teams or steering

committees, they help management in the developmentprocess.

They are also active in:

Designing system controls and monitoring and testing thesecontrols.

Ensuring the system is easy to audit.

Controls and auditability need to be built in early tominimize costs and inefficiencies later.


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THE PLAYERS


Top management



Systems analysts



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THE PLAYERS

The information systems steering committee isan executive-level committee whose duty is toplan and oversee the IS function. Consists of high level management, such as:

Controller

IS Manager

User department managers

Sets policies to govern the AIS and assure top-

management participation, guidance, and control. Attempts to encourage goal congruence and reduce

goal conflict.


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THE PLAYERS


Top management



Systems analysts



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THE PLAYERS

The project development team includes systemsspecialists, managers, accountants, auditors, and userswhose responsibility is to guide development.

Their job:

Plan each project. Monitor to ensure timely and cost-effective completion.

Ensure the human element is considered.

Communicate project status to top management and steeringcommittee.

Communicate and meet with users to: Consider ideas

Discuss progress

Eliminate surprises

The team approach produces more effective results and better

user acceptance.


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THE PLAYERS


Top management



Systems analysts



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THE PLAYERS

Systems analysts study existing systems,design new ones, and preparespecifications that are used by

programmers. They interact with technical personnel and

users to bridge the gap.

They are responsible for ensuring the system

meets user needs.


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THE PLAYERS


Top management



Systems analysts



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THE PLAYERS

Computer programmers write thecomputer programs, using the specsdeveloped by the systems analysts.

They also modify and maintaining existingprograms.


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THE PLAYERS


Top management



Systems analysts



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THE PLAYERS

External players include:

Customers

Vendors

Auditors Governmental entities

Their needs must also be met in systems

development.


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PLANNING SYSTEMS DEVELOPMENT

Several activities must be performed at varioustimes throughout the SDLC.

One of these activities is planning.

The organization should have plans for: The long range. Each systems development project.

Each phase of each systems development project.

Well discuss these plans and a number oftechniques to develop them.


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Weve all experienced the disasters that occur when wefail to plan.

When you got it home, you realized it wasnt compatiblewith your existing printer and scanner.

Furthermore, it wasnt equipped for broadband Internetaccess and you had been hoping to switch tobroadband.

By the time you spend the money and buy the parts toequip the computer to do what you want it to do, you find

that you could have bought a leading-edge computer forless money.

Suppose you bought a personal computer on impulsewithout thinking about what you wanted to do with it.


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Systems development planning is an importantstep for the following key reasons: Consistencywith the organizations strategic plan.

Efficiencyachieved through coordination of the

subsystems.

Cutting edgetechnology and techniques.

Lower costsdue to lack of duplication, wasted effort,time overruns, and cost overruns.

Adaptabilityfor future changes.


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When a system is poorly planned, a companymust often return to a prior phase and correcterrors and design flaws.

These returns are costly and result in delays,frustration, and low morale.


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Two types of systems development plansare needed:

- Individual project plans developed by the

project teams.- A master plan developed by the IS steering

committee.


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committee.


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Individual project plans contain: A cost-benefit analysis.

Developmental and operational requirements,including:

Human resources Hardware

Software

Financial resources

A schedule of activities to develop and operate thenew application.


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committee.


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Projects with highest priority are first to bedeveloped. These decisions are made by top management.

Planning horizon: About a 3-year horizon.

With updates at least 23 times/yeareven morefrequently in some companies.

The CIO should determine: How soon technologies will be in wide use.

Whether the company should adopt late or early.

What business opportunities might arise from newtechnologies.


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Planning techniques

Two techniques for scheduling and

monitoring systems development

activities are:

Program Evaluation and Review Technique

(PERT)

Gantt Charts


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Planning techniques


monitor systems development activities

are:

Program Evaluation and Review

Technique (PERT)

Gantt Charts


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A PERT diagram requires that all activities

in a project be identified along with the

activities that precede and follow them.

These activities are used to draw a PERTdiagram, which consists of a network of:

Arrowsrepresenting activities that require

time and resources. Nodesrepresenting completion and initiation

of activities.


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The critical path in a PERT diagram is the

path requiring the greatest amount of time.

If an activity on the critical path is delayed,

the whole project is delayed.

Resources may be shifted to the critical

path to reduce the delay.

SAMPLE PERT CHART


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Design

Birdhouse

(2)

(Bill)

Buy Wood

& Nails

(1)(Bill)

Buy

Paint

(1)

(Sara)

Build

Base

(2)(Bill)

Build

Roof

(1)

(Bill)

Nail

Together

(2)

(Bill)

Paint &

Decorate

(3)

(Sara)

Sell

(2)

(Sara)

SAMPLE PERT CHART For building and selling a birdhouse.

Each block contains a task and a time estimate (may

include best time, worst time, and average time). May indicate who will be responsible for the task.


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Planning techniques


monitor systems development activities

are:

Program Evaluation and Review Technique

(PERT)

Gantt Charts


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SAMPLE GANTT CHART


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SAMPLE GANTT CHART

1 2 3 4 5 6 7 8 9 10

Design birdhouse

Buy wood & nails

Buy paint

Build roofBuild base

Nail together

Paint & decorate

Sell

Period

Complete

Testing

In Development

Milestone


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FEASIBILITY ANALYSIS

The feasibility study and its updates are

used by the steering committee as the

project proceeds to decide whether to:

Terminate the project

Proceed

Proceed if specific problems are resolved


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Five aspects need to be considered during afeasibility study: Technical feasibility

Is the technology there to do it?

Operational feasibility Do we have people who can do it, and will it get used?

Legal feasibility Does it comply with legal, regulatory, and contractual

obligations?

Scheduling feasibility Can it be done in time?

Economic feasibility Will the benefits exceed the costs?


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Calculating economic feasibility costs and

benefits

Economic feasibility is probably the most important

and frequently analyzed aspect.

This examination requires a careful investigation of

costs and benefits.

It typically uses a capital budgeting model that

considers:

Cost savings and other benefits

Initial outlay costs

Operating costs

Other costs


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Benefits might include:

Cost savings.

Improved customer service, productivity,

decision making, or data processing.

Better management control.

Increased job satisfaction and employee

morale. A rigorous cost-benefit analysis is a good strategy forensuring the benefit of new information technology

exceeds the cost.


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Costs might include: Equipment costs

Initial outlay plus ongoing operating costs.

Software costs

Costs of acquiring, maintaining, supporting, and operating.

Human resource costs

Salaries, as well as costs of hiring, training, and relocating staff.

Site preparation costs.

Installation and conversion costs.

Supplies.

Overhead.

Financial charges.

The primary operating cost is maintaining the system. Makes up 6575% of the organizations system efforts.


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Capital budgeting

Most organizations use a capital budgeting

return on investment technique to evaluate

the economic merits of different systemalternatives.

There are three commonly used techniques:

Payback period

Calculates the number of years before the new savings

from the project equal the initial cost of the investment.

Select projects with shorter payback periods.


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Capital Budgeting





Payback period

Net present value (NPV)

Calculates and sums the discounted future cash flows

of the costs and benefits.

Select projects with higher positive NPV.


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Capital Budgeting





Payback period

Net present value (NPV)

Internal rate of return (IRR)

Calculates the effective interest rate that would result in

a net present value of zero for the project.

Select projects with higher IRRs.


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BEHAVIORAL ASPECTS OF CHANGE

The best system will fail without the

support of the people it serves.

So the behavioral aspects of change are

crucial.

You need to be aware of and sensitive to

the types of behavioral problems that can

result from change.


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Why behavioral problems occur

Employees will tend to view change as good if

they believe it will affect them positively and

vice versa. The Department of Defense with 3.3 million employees

has faced tremendous resistance to change in the

course of over 20 years of system integration attempts.

A more transparent system would likely exposepersonal agendas and a project protection mindset.


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To minimize adverse behavioral reactions,

it helps to understand why resistance

occurs:

Personal characteristics and background Employees are more likely to accept change if they are:

Young;

Highly educated; or

Comfortable with technology.


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occurs:

Personal characteristics and background Manner in which change is introduced

The rationale used to sell the system may need to vary

with the job responsibilities of the employees involved.


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occurs:


Experience with prior changes Fool me once, shame on me . . .

Lets see if I even give you asecond chance.


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To minimize adverse behavioral reactions,it helps to understand why resistance

occurs:


Experience with prior changes

Top management support

Communication


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To minimize adverse behavioral reactions,it helps to understand why resistance

occurs:


Experience with prior changes

Top management support

Communication Biases and natural resistance to change

Disruptive nature of the change process

Disturbances often create

negative feelings.


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How people resist AIS changes

Resistance to change often takes one of

three forms:

Aggression

Behavior intended to destroy, cripple, or weaken the

systems effectiveness.

Examples: Increased error rates, disruptions, or

deliberate sabotage.


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three forms:

Aggression

Projection

Blaming the new system for any and every unpleasant

occurrence, i.e., the system becomes a scapegoat. To preserve the integrity of the system, these criticisms

must be controlled or answered.


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three forms:

Aggression

Projection

Avoidance

If I dont use this thing, maybe it will go away!

At Davis Controls, the CEO eventually had to

terminate employees who avoided using a new

information system.



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Reactions to change can be improved byobserving the following guidelines:

Meet users needs with respect to the form,

content, and volume of system output. Keep communication lines open. Managers

and users should be fully informed about:

What changes are being made

Why

How it will benefit them

Who to contact with questions



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Maintain a safe and open atmosphere. If employees become hostile, its an uphill battle

you probably wont win.

Obtain management support.Allay fears.

To the extent possible, reassure employees that

no major job losses or responsibility shifts will

occur. If employees are terminated, severance pay and

outplacement services should be provided.



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Solicit user participation. It is ego enhancing, challenging, and intrinsically

satisfying.

Users who participate will be more committed to

using the system.

Provide honest feedback.

Explain which suggestions are and are not being

used and why. Make sure users understand the system.

Dont underestimate training needs.



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Humanize the system. Employees shouldnt feel the computer is

controlling them or has usurped their positions.

Describe new challenges and opportunities.

The system can provide greater job satisfactionand increased opportunities.

Reexamine performance evaluation. Are performance standards and criteria realistic in

light of the change? Test the systems integrity.

It important to minimize bad impressions



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Avoid emotionalism. Emotional issues should be allowed to cool, handled in

a non-confrontational manner, or sidestepped.

Present the system in the proper context.

Address the concerns of the people to whom youre

speaking, not the concerns of management or

developers.

Control the users expectations.

Dont oversell, and be realistic.

Keep the system simple.

Avoid complex systems that cause radical changes.



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Ignoring the preceding steps can leave tobehavior issues that are difficult or

impossible to reverse.

SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS

When a new or improved system isneeded, a written request for systems

development is prepared. That request

describes: The current systems problems.

The reasons for the proposed changes.

The goals and objectives of a proposedsystem.

The anticipated benefits and costs.

SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS

The project development team will conductthe systems analysis in five steps:

Initial investigation

Systems survey

Feasibility study

Information needs and systems requirements

Systems analysis report

SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS

The project development team will conductthe systems analysis in five steps


Systems survey

Feasibility study




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SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS

The initial investigation is conducted to: Gain a clear picture of the problem or need.

Determine the viability of the project and

expected costs and payoffs.


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SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS

The initial investigation is conducted to: Gain a clear picture of the problem or need.

Determine the viability of the project and

expected costs and payoffs. Evaluate the scope and nature of the new

AIS.

Recommend whether to proceed.

Either: Initiate the project as proposed.

Modify it.

Abandon it.

SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS

If the project is approved:A proposal to conduct systems analysis is

prepared.

The project is assigned a priority and addedto the master plan.

The development team begins a survey of the

existing AIS.

The proposal will be modified as more

information becomes available.

SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS

The project development team will conductthe systems analysis in five steps


Systems survey Feasibility study



SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS

A systems survey involves an extensive study of thecurrent AIS which could take weeks or months.Objectives are: Gain a thorough understanding of:

Company operations, policies, and procedures.

Data and information flow.

AIS strengths and weaknesses.

Available hardware, software, and personnel.

Make preliminary assessments of current and future

processing needs, and determine extent and nature ofneeded changes.

Develop working relationships with users and build support.

Collect data that identify user needs, conduct a feasibilityanalysis, and make recommendations to management.

SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS

Data can be gathered from: Employees.

Documentation such as organization charts

and procedure manuals. External sources such as:

Consultants

Customers

Suppliers

Industry associations

Government agencies

SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS

Four common methods of gathering dataare:

Interviews

Questionnaires Observation

System documentation

SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS


Interviews



SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS

Advantages of interviews: Can answer why questions.

Can allow for follow-up and clarification.

Provides opportunity to build positive relationships

with interviewees and support for new system.

Disadvantages of interviews:

Time-consuming.

Expensive. Personal biases or self-interest may produce

inaccurate information.

SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS

When you do interviews: Make an appointment.

Explain the purpose ahead of time.

Indicate the amount of time needed.

Be on time. Be familiar with the interviewees responsibilities.

Make notes on points to cover.

Put the interviewee at ease and let him/her do thetalking.

Pay attention to nonverbal cues. Take notes and augment them with impressions after

the interview.

Request permission to tape critical interviews.

SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS


Interviews



SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS

Questionnaires can be used when: The amount of information to be gathered is

small and well defined.

The information is to be obtained from manypeople or from those who are remotely

located.

The information is intended to verify data from

other sources.

SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS

Advantages of questionnaires: Can be anonymous.

Not time-consuming to complete.

Inexpensive.

Allows the subject time to think about responses.

Disadvantages of questionnaires: Does not allow in-depth questions or answers.

Does not allow follow-up or clarification.

Does not build relationships.

Difficult to develop.

May be ignored or completed superficially.

SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS


Interviews



SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS

Advantages of observations: Can verify how the system actually works

rather than how it should work.

Results in greater understanding of systems.

Disadvantages of observations:

Time-consuming.

Expensive.

Difficult to interpret.

People may alter behavior while beingobserved.

SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS

When you do observations: Identify what is to be observed and estimate

the time required.

Obtain permission. Explain what will be done and why.

Dont make value judgments.

Take notes and document impressions ASAP.

SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS


Interviews



SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS

Advantages of systems documentation: Describes how the system shou ldwork.

Written form facilitates review and analysis.

Disadvantages of systems documentation:

Time consuming.

May be elusive.

When you examine systems documentation: Keep in mind that the system doesnt always work as

it should per the documentation.

If documentation is unavailable, it may be worthwhileto develop it.


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SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS

Another form of documentation is asystem model:

Physical modelsillustrate how a systemfunctions by describing: Flow of documents.

Computer processes performed and the peopledoing them.

Equipment used.

Any other physical elements.

Logical modelsillustrate what is being doneregardless of how the flow is accomplished.

SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS

When documentation is complete, analyzethe existing system:

Evaluate the AISs strengths and weaknesses

to develop ideas for designing and structuringthe new AIS.

Try to retain strengths.

Correct weaknesses.

Sometimes, you need revolutionary, rather

than evolutionary change.

Called reengineering.

SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS

At the end of this phase, prepare systemssurvey report:

Outlines and documents the data gathered.

Provides recommendations that result fromthe systems survey.

SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS






SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS

After the systems survey, a more thoroughfeasibility analysis is conducted.

This analysis is updated regularly as the

project proceeds and costs and benefitsbecome clearer.

SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS




Information needs and systems

requirements Systems analysis report

SYSTEMS ANALYSIS


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SYSTEMS ANALYSIS

Once a project clears the feasibility hurdle, the companyidentifies the information needs of AIS users and

documents systems processes, including:

- Processes

Describes what is to be doneand by whom.

SYSTEMS ANALYSIS


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S S S S S



- Processes

- Data elements

Describes name, size, format,

source, and significance ofnecessary data elements.

SYSTEMS ANALYSIS


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- Processes

- Data elements- Data structure A preliminary structure showing

how the data elements will be

organized into logical records.

SYSTEMS ANALYSIS


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- Processes

- Data elements- Data structure

- Outputs Layouts of system outputs and a

description of their purpose,

frequency, and distribution.

SYSTEMS ANALYSIS


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- Processes


- Outputs

- Inputs A copy of system inputs and a

description of their contents,

source, and who is responsiblefor them.

SYSTEMS ANALYSIS


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- Processes


- Outputs

- Inputs

- Constraints

A description of deadlines,

schedules, security requirements,

staffing limitations, and legalrequirements.

SYSTEMS ANALYSIS


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- Processes


- Outputs

- Inputs

- Constraints

- Controls Controls that are needed toensure accuracy and reliability.

SYSTEMS ANALYSIS


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- Processes


- Outputs

- Inputs

- Documentation constraints

- Controls

- Reorganizations Changes in staffing, job

functions, etc., that would be

necessary.

SYSTEMS ANALYSIS


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Issues: There is much to be specified, even for a

simple AIS.

It may be difficult to get employees toaccurately articulate their needs.

Errors are best caught early, as the cost to

correct them increases significantly the farther

you are into the project.

SYSTEMS ANALYSIS


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Systems objectives and constraints Many entities take a systems approachto

determining information needs and systems

requirements. Problems and alternatives are viewed from

the standpoint of the entire organizationas

opposed to a single department.

SYSTEMS ANALYSIS


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Systems objectives must be identified, soanalysts and users can focus on those elements

most vital to success of the AIS. These may

include:

- Usefulness

Able to help users make

decisions.

SYSTEMS ANALYSIS


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include:

- Usefulness

- Economy

Benefits exceed costs.

SYSTEMS ANALYSIS


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include:

- Usefulness

- Economy

- Reliability

Data is processed accurately

and reliably.

SYSTEMS ANALYSIS


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include:

- Usefulness

- Economy

- Reliability

- Availability You can access it when you

need it.

SYSTEMS ANALYSIS


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include:

- Usefulness

- Economy

- Reliability

- Availability- Timeliness

More critical information is

provided first.

SYSTEMS ANALYSIS


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include:

- Usefulness

- Economy

- Reliability


- Customer service

Efficient and courteous.

SYSTEMS ANALYSIS


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include:

- Usefulness

- Economy

- Reliability


- Customer service

- Capacity

Can handle peak periods.

SYSTEMS ANALYSIS


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include:

- Usefulness

- Economy

- Reliability


- Customer service

- Capacity

- Ease of use

SYSTEMS ANALYSIS


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include:

- Usefulness

- Economy

- Reliability


- Customer service

- Capacity

- Ease of use

- Flexibility

Can accommodate changes.


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SYSTEMS ANALYSIS


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include:

- Usefulness

- Economy

- Reliability


- Customer service

- Capacity

- Ease of use

- Flexibility

- Tractability

- Auditability

- Security Available only toauthorized users.

SYSTEMS ANALYSIS


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There are often trade-offs between objectives. Organizational constraints make it impossible to

develop all parts of an AIS simultaneously.

You divide it into modules that are analyzed,

developed, and installed independently.

When changes are made, only the affected modules

need to be changed.

The modules should be properly integrated into a

workable system.

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Success often depends on the projectteams ability to cope with organizational

constraints, including:

Requirements of governmental agencies. Managerial policies and guidelines.

Lack of sufficient, qualified staff.

Capabilities and attitudes of users.Available technology.

Limited financial resources.

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Strategies for determiningrequirements:

One or more of the following four strategies

are used to determine AIS requirements: Ask users what they need

This is the simplest and fastest strategy.

But many people dont realize or understand their true

needs.

Its sometimes better to ask them what decisions they

make and what processes they are involved in.

Users also need to think beyond their current

information needs.

SYSTEMS ANALYSIS


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Strategies for determiningrequirements:



Analyze existing systems

Internal and external systems should be analyzed to

avoid reinventing the wheel.

SYSTEMS ANALYSIS


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Strategies for DeterminingRequirements:




Examine existing system use

Certain modules:

May not be used as intended

May be augmented by manual tasks

May be avoided altogether Helps determine whether the system really needs to be

simply modified rather than replaced.

SYSTEMS ANALYSIS


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Strategies for DeterminingRequirements:




Examine existing system use

Create a prototype

Entails roughing out a system for users to critique.

When they see something on a screen, its easier to

identify what they like and dont like.

Goes through iterations of improving and reviewing

with users until users agree on their needs.

SYSTEMS ANALYSIS


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Documentation and approval of userrequirements:

Detailed requirements for the new AIS shouldbe created and documented.

How to produce the required features isdetermined during the design phases of the SDLC.

The requirements list should be supported bysample input and output forms and charts that

make it easier to conceptualize. A nontechnical summary is often prepared for

management.

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Once user requirements have beendetermined and documented, the project

team:

Meets with users. Explains the requirements.

Obtains their agreement and approval.

When an agreement is reached, usermanagement should sign off on the

requirements.

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SYSTEMS ANALYSIS


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A go-no-go decision is usually made threetimes during systems analysis:

During the initial investigation to determine

whether to go ahead with a systems survey.At the end of the feasibility study to determine

whether to proceed with the information

requirements step.

At the completion of the analysis phase todecide whether to proceed to the next phase

(conceptual design).


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SUMMARY


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Youve learned about the five phases in thesystems development life cycle, with a particularemphasis on systems analysis.

Youve learned who the players are in thesystems development process.

Youve learned about various techniques thatare used to plan the development of a system.

Youve reviewed some techniques fordetermining system feasibility.

Youve learned about behavioral responses tosystems changes and how dysfunctional

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Accounting Information System Romney Ch18

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