Accounting information systems 11e romney steinbart chapter 18

C HAPTER 18 Introduction to Systems Development and Systems Analysis © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart of 153 INTRODUCTION • Questions to be addressed in this chapter include: – What are the phases in the systems development life cycle? – Who are the individuals involved in systems development? – What techniques are used to plan the development of a system? – How you determine whether a particular system is feasible? – How people respond to systems changes, and how can dysfunctional behavior be minimized? © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart of 153 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 © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart of 153 INTRODUCTION • 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 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 © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart of 153 INTRODUCTION • 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 © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart of 153 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 © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart of 153 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 © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart of 153 SYSTEMS DEVELOPMENT LIFE CYCLE • The five stages in the systems development life cycle are: – – – – – Systems analysis Conceptual design Physical design Implementation and conversion Operation and maintenance © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart of 153 SYSTEMS DEVELOPMENT LIFE CYCLE • The five stages in the systems development life cycle are: – – – – – Systems analysis Conceptual design Physical design Implementation and conversion Operation and maintenance © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart of 153 SYSTEMS DEVELOPMENT LIFE CYCLE • 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 © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 10 of 153 SYSTEMS ANALYSIS • Systems objectives must be identified, so analysts and users can focus on those elements most vital to success of the AIS These may include: - Usefulness Economy Reliability Availability Timeliness Customer service © 2008 Prentice Hall Business Publishing - Capacity Ease of use Flexibility Tractability Auditability Accounting Information Systems, 11/e Romney/Steinbart 139 of 153 SYSTEMS ANALYSIS • Systems objectives must be identified, so analysts and users can focus on those elements most vital to success of the AIS These may include: - Usefulness Economy Reliability Availability Timeliness Customer service © 2008 Prentice Hall Business Publishing - Capacity Ease of use Flexibility Tractability Auditability Security • Available only to Accounting Information Systems, 11/e authorized users Romney/Steinbart 140 of 153 SYSTEMS ANALYSIS • 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 © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 141 of 153 SYSTEMS ANALYSIS • Success often depends on the project team’s 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 © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 142 of 153 SYSTEMS ANALYSIS • Strategies for determining requirements: – 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 don’t realize or understand their true needs It’s 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 © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 143 of 153 SYSTEMS ANALYSIS • Strategies for determining requirements: – One or more of the following four strategies are used to determine AIS requirements: • Ask users what they need • Analyze existing systems  Internal and external systems should be analyzed to avoid reinventing the wheel © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 144 of 153 SYSTEMS ANALYSIS • Strategies for Determining Requirements: – One or more of the following four strategies are • modules: used toCertain determine AIS requirements: – May not be used as intended • Ask users they need – Maywhat be augmented by manual tasks – May be avoided altogether • Analyze existing systems • Helpsexisting determinesystem whether use the system really needs to be • Examine simply modified rather than replaced © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 145 of 153 SYSTEMS ANALYSIS • Strategies for Determining Requirements: – One or more of the following four strategies are used to determine AIS requirements: • Ask users what they need • Entails roughing out a system for users to critique • Analyze existing systems • When they see something on a screen, it’s easier to • Examine existing system usedon’t like identify what they like and • Goes through iterations of improving and reviewing • Create a prototype with users until users agree on their needs © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 146 of 153 SYSTEMS ANALYSIS • Documentation and approval of user requirements: – Detailed requirements for the new AIS should be created and documented • How to produce the required features is determined during the design phases of the SDLC • The requirements list should be supported by sample input and output forms and charts that make it easier to conceptualize • A nontechnical summary is often prepared for management © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 147 of 153 SYSTEMS ANALYSIS • Once user requirements have been determined and documented, the project team: – Meets with users – Explains the requirements – Obtains their agreement and approval • When an agreement is reached, user management should sign off on the requirements © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 148 of 153 SYSTEMS ANALYSIS • The project development team will conduct the systems analysis in five steps: – – – – – Initial investigation Systems survey Feasibility study Information needs and systems requirements Systems analysis report © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 149 of 153 SYSTEMS ANALYSIS • The last step in systems analysis is the systems analysis report – Summarizes and documents the activities – Serves as a repository of data from which designers can draw – Outlines: • • • • • • Goals and objectives of the new system Scope of the project How the new system fits into the company’s master plan User processing requirements and information needs Feasibility analysis Recommendations for the new system © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 150 of 153 SYSTEMS ANALYSIS • A go-no-go decision is usually made three times 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 to decide whether to proceed to the next phase (conceptual design) © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 151 of 153 SYSTEMS ANALYSIS • When systems analysis is completed, the project can move on to: – – – – Conceptual design phase Physical design phase Implementation and conversion Operation and maintenance © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 152 of 153 SUMMARY • You’ve learned about the five phases in the systems development life cycle, with a particular emphasis on systems analysis • You’ve learned who the players are in the systems development process • You’ve learned about various techniques that are used to plan the development of a system • You’ve reviewed some techniques for determining system feasibility • You’ve learned about behavioral responses to systems changes and how dysfunctional behavior can be minimized © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 153 of 153 ... will be forwarded to the information systems steering committee © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/ Steinbart 18 of 153 SYSTEMS DEVELOPMENT LIFE... Business Publishing Accounting Information Systems, 11/e Romney/ Steinbart of 153 SYSTEMS DEVELOPMENT LIFE CYCLE • The five stages in the systems development life cycle are: – – – – – Systems analysis... Business Publishing Accounting Information Systems, 11/e Romney/ Steinbart of 153 SYSTEMS DEVELOPMENT LIFE CYCLE • The five stages in the systems development life cycle are: – – – – – Systems analysis