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©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Accounting Information Systems9th Edition
Marshall B. Romney
Paul John Steinbart
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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AIS Development Strategies
Chapter 17
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Learning Objectives
1. Describe how organizations purchase application software, vendor services, and hardware.
2. Explain how information system departments develop custom software.
3. Explain how end-users develop, use, and control computer-based information systems.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Learning Objectives
4. Explain why organizations outsource their information systems, and evaluate the benefits and risks of this strategy.
5. Explain the principles and challenges of business process reengineering.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Learning Objectives
6. Describe how prototypes are used to develop an AIS, and discuss the advantages and disadvantages of doing so.
7. Explain what computer-aided software engineering is and how it is used in systems development.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Introduction
Ann Christy was elated that the new system Shoppers Mart (SM) needed was approved.
She needed answers to the following questions: Was the software she needed available for
her to purchase? If so, how should she approach the process of buying hardware and software and selecting a vendor?
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Introduction
How do companies go about developing software in-house, and is this the best approach for SM?
How extensively should the system make use of end-user-developed software?
If the company decided to develop the system in-house, should it try and speed up the development process by using prototyping or computer-assisted software engineering?
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Introduction
Should SM just make the needed improvements to its existing system, or should it consider reengineering its business processes and then develop a system to support the new processes?
Was outsourcing the information system a viable alternative to obtaining a new system? Did the benefits outweigh its risks?
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Introduction
This chapter discusses three ways to obtain a new information system: purchasing prewritten software, developing software in-house, and hiring an outside company (outsourcing).
It also presents ways of speeding up or improving the development process – business process reengineering, prototyping and computer-aided software engineering (CASE) tools.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Learning Objective 1
Describe how organizations purchase application software, vendor services, and hardware.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Purchase Software
Canned software is written by software development companies and is sold on the open market to a broad range of users with similar requirements.
Turnkey systems are a combination of software and hardware sold as a package. The vendor installs the entire system and user needs only to “turn the key”.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Purchase Software, continued
The Internet has given companies a new way to acquire software:
Application service providers (ASPs) host Web-based software on their computers and deliver the software to their clients over the Internet.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Purchasing Software and The SDLC Companies that buy rather than
develop AIS software still go through the systems development life cycle (SDLC).
1. Systems analysis2. Conceptual design3. Physical design4. Implementation and conversion5. Operation and maintenance
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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The Systems Acquisition Process
Will packagemeet needs?
Developsoftwareinternally
Send RFP forhardware,
if necessary
Evaluateproposal
No
Yes
Investigatesoftwarepackages
Can packagebe modified?
Send RFP forsoftware and
hardware
No
Yes
Select bestcombination
Yes
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Learning Objective 2
Explain how information system departments develop custom software.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Development by In-House IS Department
Most often, organizations develop their own custom software, because canned software that fit their specific needs is not available.
Developing custom software is difficult and error-prone.
It also consumes a great deal of time and resources.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Custom Software Development by an Outside Company
When contracting with an outside organization, a company should maintain control over the development process. Some guidelines:
• Carefully select a developer
• Sign a contract
• Plan and monitor each step
• Maintain effective communication
• Control all costs
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Learning Objective 3
Explain how end users develop, use, and control computer-based information systems.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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End-User-Developed Software End-user computing (EUC) is the hands-on
development, use, and control of computer-based information systems by users.
With the advent of inexpensive PCs and powerful, inexpensive software, users began developing their own systems to create and store data, access and download company data, and share data and computer resources in networks.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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End-User-Developed Software Examples of end user development uses:
• Retrieving information from company databases to produce simple reports or to answer one-time queries
• Performing “what if” sensitivity or statistical analyses
• Developing applications using prewritten software (spreadsheet or database system)
• Preparing schedules and lists, such as depreciation schedules, accounts receivable aging, and loan amortizations
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Benefits of End-User-Developed Software
Benefits of End-User Computing
User creation, control, and implementation Systems that meet user needs Timeliness
Freeing up IS resources Versatility and ease of use
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Risks of End-User-Developed Software
Risks of End-User Computing Logic and development errors
Inadequately tested applications Inefficient systems
Poorly controlled and documented systems Systems incompatibility Duplication of systems
Increased costs
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Managing and Controlling End-User Computing
Organizations use several different approaches to mange and control end-user computing. For example, a help desk can encourage, support, coordinate and control end-user activities.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Functions of a Help Desk
What are some duties of the help desk?– Providing hot-line assistance to help resolve
problems– Serving as a clearinghouse for information,
coordination, and assistance training end users, and providing corresponding technical maintenance and support
– Evaluating new end-user hardware and software products
– Assisting with application development– Developing and implementing standards– Controlling corporate data
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Learning Objective 4
Explain why organizations outsource their information systems, and evaluate the benefits and risks of this strategy.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Outsource the System
What is outsourcing?It is hiring an outside company to
handle all or part of an organization’s data processing activities.
In a mainframe outsourcing agreement, the outsourcers buy their client’s computers and hire all or most of the client’s employees.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Outsource the System
In a client/server or PC outsourcing agreement, an organization outsources a particular service, a segment of its business, a particular function, or PC support.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Outsource the System
Benefits of OutsourcingA business and information solution
Asset utilization
Access to greater expertise and more advanced technology
Lower costs Improved development time
Elimination of peaks and valleys usage Facilitation of downsizing
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Outsource the System
Risks of Outsourcing Inflexibility
Loss of control of system and/or data Reduced competitive advantage
Locked-in system Unfulfilled goals
Possibility of poor service
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Learning Objective 5
Explain the principles and challenges of business process reengineering.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Business Processes Reengineering What is business process reengineering
(BPR)? It is the thorough analysis and complete
redesign of business process and information systems to achieve performance improvements.
It is a process that challenges traditional organizational values and cultures associated with underperformance.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Business Processes Reengineering BPR reduces a company to its
essential business processes and focuses on why they are done rather than on the details of how they are done.
It completely reshapes organizational work practices and information flows to take advantage of technological advancements.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Principles of Reengineering
What are the seven principles of business processing reengineering?
1. Organize around outcomes, not tasks.
2. Require those who use the output to perform the process.
3. Require those who produce information to process it.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Principles of Reengineering
4. Centralize and disperse data.
5. Integrate parallel activities
6. Empower workers, use built-in controls, and flatten the organization chart.
7. Capture data once, at its source.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Challenges Faced by Reengineering Efforts
What are some of the obstacles to reengineering efforts?
Tradition Resistance
Time requirements Risk
Lack of management support Skepticism
Retraining Controls
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Learning Objective 6
Describe how prototypes are used to develop an AIS, and discuss the advantages and disadvantages of doing so.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Prototyping
What is prototyping?– an approach to systems design in
which a simplified working model of a system is developed.
A prototype, or “first draft,” is quickly and inexpensively built and provided to users for testing.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Prototyping
What four steps are involved in developing a prototype?1. Identify basic systems requirements.
2. Develop an initial prototype that meets the agreed-on requirements.
3. Users identify changes, developers make changes, and the system is turned over to the user.
4. Use the system approved by the users.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Benefits of Prototyping
Advantages of Prototyping
Better definition of user needs Higher user involvement and satisfaction
Faster development time Fewer errors More opportunity for changes
Less costly
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Disadvantages of Prototyping
Disadvantages of Prototyping Significant user time Less efficient use of system resources
Incomplete systems development Inadequately tested and
documented systems Negative behavioral reactions
Unending development
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Learning Objective 7
Explain what computer-aided software engineering is and how it is used in systems development.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Computer-Aided Software Engineering (CASE) CASE is an integrated package of
computer-based tools that automate important aspects of the software development process.
CASE tools are used to plan, analyze, design, program, and maintain an information system.
They are also used to enhance the efforts of managers, users, and programmers in understanding information needs.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Computer-Aided Software Engineering (CASE) CASE tools do not replace skilled
designers; instead they provide a host of self-integrated tools that give developers effective support for all SDLC phases.
CASE software typically has tools for strategic planning, project and system management, database design, screen and report layout, and automatic code generation.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Computer-Aided Software Engineering (CASE)
Advantages of CASE Technology
Improved productivity Improved program quality
Cost savings Improved control procedures
Simplified documentation
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Computer-Aided Software Engineering (CASE)
Disadvantages of CASE Technology Incompatibility
CostUnmet expectations
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Case Conclusion
What did Ann Christy decide?– against outsourcing the AIS
What did she think about prototyping?– that it would not work well
What did she think about reengineering?– that the system did not need reengineering
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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Case Conclusion
What were her options?– purchase a system or design
one in-house. No matter which approach she
chose, Ann wanted to facilitate as much end-user development as was practical and useful.
©2003 Prentice Hall Business Publishing, Accounting Information Systems, 9/e, Romney/Steinbart
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End of Chapter 17