Accounting information systems 11e romney steinbart chapter 18

SYSTEMS DEVELOPMENT LIFE CYCLE• The five stages in the systems development life cycle are: – Systems analysis – Conceptual design – Physical design – Implementation and conversion – Oper

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C HAPTER 18

Introduction to Systems Development and Systems

Analysis

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• Questions to be addressed in this chapter include:

– What are the phases in the systems development

– How do people respond to systems changes, and

how can dysfunctional behavior be minimized?

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• 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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• Companies change their systems for a variety of

reasons:

– 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.

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• Developing quality, error-free software is difficult,

expensive, and time-consuming.

• Projects tend to deliver less than expected and consume more time and money.

• A KPMG survey found that 35% of all major information

systems projects were classified as runaways—

hopelessly incomplete and over budget.

– Major cause of runaways: Skimping on systems

development processes.

• Omitting basic systems development steps becomes

tempting but may lead to disaster as developers create

well-structured systems that fail to meet user needs or

solve business problems.

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• 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 or minor, most companies

go through a systems development life cycle.

• In this section, we discuss the steps in the cycle and the people

involved.

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• The five stages in the systems development life cycle are:

– Systems analysis – Conceptual design – Physical design – Implementation and conversion – Operation and maintenance

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– Systems analysis

– Conceptual design – Physical design – Implementation and conversion – Operation and maintenance

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• As organizations grow and change, they may

need 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.

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– 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.

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– Initial investigation – Systems survey

– Feasibility study

 Involves an in-depth study of the proposed

system to determine whether it’s feasible.

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– Feasibility study

– Determination of information needs and system

requirements

 Involves finding out and documenting what

users and management need.

 This is the most important aspect of

systems analysis.

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– Feasibility study – Determination of information needs and system

requirements

– Delivery of systems requirements

 Involves preparation of a report

summarizing the systems analysis work.

 This report is submitted to the information

systems steering committee.

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– Systems analysis

– Conceptual design

– Physical design – Implementation and conversion – Operation and maintenance

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• In the conceptual design phase, the company

decides how to meet user needs.

• Tasks in this phase include :

– Identify and evaluate design alternatives

 Possibilities include:

 Buying software

 Developing in-house

 Outsourcing

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– 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.

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– Identify and evaluate design alternatives – Develop design specifications

– Deliver conceptual design requirements

 These requirements will be forwarded to the information systems steering committee.

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– Systems analysis – Conceptual design

– Physical design

– Implementation and conversion – Operation and maintenance

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• In the physical design phase, the broad,

user-oriented requirements of the conceptual design

are translated into detailed specifications that

can be used by programmers to code the

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– Systems analysis – Conceptual design – Physical design

– Implementation and conversion

– Operation and maintenance

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• This is the capstone phase during which everything

comes 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 existing employees relocated.

– Test the system and make any needed modifications.

– Complete the documentation.

– Convert from the old to the new system.

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– Systems analysis – Conceptual design – Physical design – Implementation and conversion

– Operation and maintenance

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• Once the system is up and running, operations

and 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 system

replacement is necessary, and the systems

development 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 this

chapter.

• Additionally, the first phase in the SDLC, systems

analysis, will be discussed in more detail.

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THE PLAYERS

• Many people are involved in developing and

successfully 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

successfully implement an AIS, including:

• Accountants

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THE PLAYERS

• Top management’s role in systems development

is 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.

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THE PLAYERS

• User management needs to:

– Determine information requirements for

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THE PLAYERS

• Accountants

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THE PLAYERS

• Accountants also play an important role in

systems 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 development process.

– They are also active in:

• Designing system controls and monitoring and testing these controls.

• Ensuring the system is easy to audit.

– Controls and “auditability” need to be built in early to

minimize costs and inefficiencies later.

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THE PLAYERS

• Accountants

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THE PLAYERS

• The information systems steering committee is

an executive-level committee whose duty is to

plan 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

• Accountants

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THE PLAYERS

• The project development team includes systems

specialists, managers, accountants, auditors, and users

whose 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 steering

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THE PLAYERS

• Accountants

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THE PLAYERS

• Systems analysts study existing systems, design new ones, and prepare specifications 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

• Accountants

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THE PLAYERS

• Computer programmers write the computer programs, using the

specs developed by the systems analysts.

• They also modify and maintaining existing programs.

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THE PLAYERS

• Accountants

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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 various

times 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.

• We’ll discuss these plans and a number of

techniques to develop them.

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• We’ve all experienced the disasters that occur when we

fail to plan.

• When you got it home, you realized it wasn’t compatible

with your existing printer and scanner.

• Furthermore, it wasn’t equipped for broadband Internet

access and you had been hoping to switch to

broadband.

• By the time you spend the money and buy the parts to

equip the computer to do what you want it to do, you find that you could have bought a leading-edge computer for

less money.

• Suppose you bought a personal computer on impulse

without thinking about what you wanted to do with it.

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• Systems development planning is an important

step for the following key reasons:

– Consistency with the organization’s strategic

plan.

– Efficiency achieved through coordination of the

subsystems.

– Cutting edge technology and techniques.

– Lower costs due to lack of duplication, wasted

effort, time overruns, and cost overruns.

– Adaptability for future changes.

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• When a system is poorly planned, a company

must often return to a prior phase and correct

errors and design flaws.

• These returns are costly and result in delays,

frustration, and low morale.

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• Two types of systems development plans are needed:

- Individual project plans developed by the project

teams.

- A master plan developed by the IS steering

committee.

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- Individual project plans developed by the project

teams.

- A master plan developed by the IS steering

committee.

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• Individual project plans contain:

the new application.

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- Individual project plans developed by the project

teams.

- A master plan developed by the IS steering

committee.

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• A master plan specifies:

– What the system will consist of – How it will be developed.

– Who will develop it.

– How needed resources will be acquired.

– Where the AIS is headed.

• It also provides:

– Status of projects in process.

– Prioritization of planned projects and criteria for

establishing priorities.

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• Projects with highest priority are first to be

developed.

– These decisions are made by top management.

• Planning horizon:

– About a 3-year horizon.

– With updates at least 2–3 times/year—even more

frequently 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 new

technologies.

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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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