Adv ais other dev approaches

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Adv ais other dev approaches

  1. 1. T OPIC SEVEN Other AIS Development Approaches© 2012 UMT Advanced Accounting Information Systems 1
  2. 2. INTRODUCTION • We’ll also discuss how to hasten or improve the development process through: – Business process reengineering – Prototyping – Computer-aided software engineering (CASE) tools© 2012 UMT Advanced Accounting Information Systems 2
  3. 3. BUSINESS PROCESS REENGINEERING • Business process reengineering (BPR) is the analysis and redesign of business processes and information systems to achieve significant performance improvements. – Reduces a company to its essential business processes. – Reshapes organizational work practices and information flows to take advantage of technological advancements.© 2012 UMT Advanced Accounting Information Systems 3
  4. 4. BUSINESS PROCESS REENGINEERING • BPR: – Simplifies the system. – Makes it more effective. – Improves a company’s quality and service. • BPR software has been developed to help automate many BPR tasks.© 2012 UMT Advanced Accounting Information Systems 4
  5. 5. BUSINESS PROCESS REENGINEERING • Michael Hammer has set forth several principles that help organizations successfully reengineer business processes: - Organize around outcomes, not tasks. • DO AWAY WITH: Assigning different parts of a business process to different people, with the resulting handoffs, delays, and errors. • INSTEAD: Each person’s job is designed around an objective, outcome, or process rather than a task needed to complete a process.© 2012 UMT Advanced Accounting Information Systems 5
  6. 6. BUSINESS PROCESS REENGINEERING • Michael Hammer has set forth several principles that help organizations successfully reengineer business processes: - Organize around outcomes, not tasks. - Require those who use the output to perform the process.© 2012 UMT Advanced Accounting Information Systems 6
  7. 7. BUSINESS PROCESS REENGINEERING Michael Hammer has set forth several principles that help organizations successfully reengineer business processes: - Organize around outcomes, not tasks. - Require those who use the output to perform the process. - Require those who produce information to process it.© 2012 UMT Advanced Accounting Information Systems 7
  8. 8. BUSINESS PROCESS REENGINEERING • You centralize operations to achieve economies of scale and eliminate redundancy. • Michael Hammer has set forth several principles • You decentralize operations to be more that help organizations successfully reengineer responsive to customers and provide better business processes: service - Organizetechnology, you don’t tasks. to choose. • With around outcomes, not have - Require those who use the output to perform the – Corporate-wide databases centralize data. process. – Telecommunications technology disburses it to the organization. - Require those who produce information to process it. - Centralize AND disperse data.© 2012 UMT Advanced Accounting Information Systems 8
  9. 9. BUSINESS PROCESS REENGINEERING • Michael Hammer has set forth several principles that help organizations successfully reengineer business processes: - Organize around outcomes, not tasks. - Require those developing a new product, include thethe Example: In who use the output to perform on process. development team at least one person from each involved - Require those so the right hand will know what the left hand department, who produce information to process it. is doing and the process will be smoothly integrated. - Centralize AND disperse data. - Integrate parallel activities.© 2012 UMT Advanced Accounting Information Systems 9
  10. 10. BUSINESS PROCESS REENGINEERING • Michael Hammer has set forth several principles that help organizations successfully reengineer business traditional system, there is a layer of worker • In a processes: bees and several layers of manager bees, - Organize around outcomes, not tasks. auditor bees, and controller bees. - Requirereengineered system, the people who do the • In a those who use the output to perform the process. have decision-making responsibility. work - Require those who produceenables their decision – Information technology information to process it. - accuracy. Centralize AND disperse data. - Integrate parallel activities. process itself. – Controls are built into the - Empower workers, use built-in controls, and flatten the organization chart.© 2012 UMT Advanced Accounting Information Systems 10
  11. 11. BUSINESS PROCESS REENGINEERING • Michael Hammer has set forth several principles that help organizations successfully reengineer business processes: - Organize around outcomes, not tasks. - Require those who use the output to perform the process. - Require those who produce information to process it. - Centralize AND disperse data. • Instead of having each functional area running its own AIS - Integrateentering the same data, use source data automation, and parallel activities. - Empoweretc. to capture data electronically at theflatten and EDI, workers, use built-in controls, and source the organization chart. it needs to be used. disburse it to where - Capture data once—at its source.© 2012 UMT Advanced Accounting Information Systems 11
  12. 12. BUSINESS PROCESS REENGINEERING • Underlying reengineering is the efficient and effective use of the latest information technology, e.g.: – Radio- and satellite-based communications. – Powerful handheld computers. – Image processing that lets multiple users handle a document simultaneously. – Active documents.© 2012 UMT Advanced Accounting Information Systems 12
  13. 13. BUSINESS PROCESS REENGINEERING • Challenges faced by reengineering efforts: – Many BPR efforts fail or fall short of their objectives. A company must overcome the following obstacles: • Tradition • “We’ve always done it this way!” • Success requires changes in culture and beliefs.© 2012 UMT Advanced Accounting Information Systems 13
  14. 14. BUSINESS PROCESS REENGINEERING • Challenges Faced by Reengineering Efforts: – Many BPR efforts fail or fall short of their objectives. A company must overcome the following obstacles: • Tradition • Resistance • Change is always met with resistance. • Requires continual reassurance, persuasion, and support.© 2012 UMT Advanced Accounting Information Systems 14
  15. 15. BUSINESS PROCESS REENGINEERING • Challenges Faced by Reengineering Efforts: – Many BPR efforts fail or fall short of their objectives. A company must overcome the following obstacles: • Tradition • Resistance • Time and cost requirements • Two or more years are required to complete BPR.© 2012 UMT Advanced Accounting Information Systems 15
  16. 16. BUSINESS PROCESS REENGINEERING • Challenges faced by reengineering efforts: – Many BPR efforts fail or fall short of their objectives. A company must overcome the following obstacles: • Tradition • Resistance • Time and cost requirements • Lack of management support • Managers are nervous about the “big hype—few results” syndrome. • Without their support, the effort will fail.© 2012 UMT Advanced Accounting Information Systems 16
  17. 17. BUSINESS PROCESS REENGINEERING • Challenges Faced by Reengineering Efforts: – Many BPR efforts fail or fall short of their objectives. A company must overcome the following obstacles: • Tradition • Resistance • Time and cost requirements • Lack of management support • Skepticism • BPR is sometimes viewed as just the same picture in a different frame.© 2012 UMT Advanced Accounting Information Systems 17
  18. 18. BUSINESS PROCESS REENGINEERING • Challenges Faced by Reengineering Efforts: – Many BPR efforts fail or fall short of their objectives. A company must overcome the following obstacles: • Tradition • Resistance • Time and cost requirements • Lack of management support • Skepticism • Retraining • The necessary retraining costs time and dollars.© 2012 UMT Advanced Accounting Information Systems 18
  19. 19. BUSINESS PROCESS REENGINEERING • Challenges faced by reengineering efforts: – Many BPR efforts fail or fall short of their objectives. A company must overcome the following obstacles: • Tradition • Resistance • Time and cost requirements • Lack of management support • Skepticism • Retraining • Controls • Cannot skip the inclusion of controls to ensure reliability and integrity.© 2012 UMT Advanced Accounting Information Systems 19
  20. 20. INTRODUCTION • We’ll be discussing how to obtain a new information system by: – Purchasing prewritten software – Developing software in-house – Outsourcing • We’ll also discuss how to hasten or improve the development process through: – Business process reengineering – Prototyping – Computer-aided software engineering (CASE) tools© 2012 UMT Advanced Accounting Information Systems 20
  21. 21. PROTOTYPING • Prototyping is an approach to systems design in which a simplified working model of a system is developed. – The prototype (first draft) is built quickly at low cost and provided to users for experimentation. – Playing with the prototype allows users to determine what they do and do not like. – Developers modify the system in response to user comments and re-present it to them. – The iterative process continues until users are satisfied that the system meets their needs.© 2012 UMT Advanced Accounting Information Systems 21
  22. 22. PROTOTYPING • The basic premise is that it’s easier for people to express what they like or dislike than to imagine what they want in a system. – In another words, it helps to have a straw man to aim at. – Even a simple system that is not fully functional demonstrates features far better than graphics and verbiage.© 2012 UMT Advanced Accounting Information Systems 22
  23. 23. PROTOTYPING • Developers who use prototyping still go through the systems development life cycle. • But prototyping allows them to expedite some analysis and design. • For example, prototyping captures user needs and helps developers and users make many conceptual and physical design decisions. • Current practice leans heavily toward prototyping so that projects can be completed quickly.© 2012 UMT Advanced Accounting Information Systems 23
  24. 24. PROTOTYPING • Four steps are involved in developing a prototype: – STEP ONE: Identify basic requirements – STEP TWO: Develop an initial prototype – STEP THREE: Repeated iterations – STEP FOUR: Use the system© 2012 UMT Advanced Accounting Information Systems 24
  25. 25. PROTOTYPING • Four steps are involved in developing a prototype: – STEP ONE: Identify basic requirements – STEP TWO: Develop an initial prototype – STEP THREE: Repeated iterations – STEP FOUR: Use the system© 2012 UMT Advanced Accounting Information Systems 25
  26. 26. PROTOTYPING • The first step is to identify basic requirements by meeting with users to agree on the size and scope of the system and decide what it should include and exclude. – Developer and users also determine: • Decision-making and transaction processing outputs. • Inputs and data needed to produce those outputs. – The emphasis is on what outputs should be produced rather than how.© 2012 UMT Advanced Accounting Information Systems 26
  27. 27. PROTOTYPING – The developer must ensure: • User expectations are realistic. • Their basic information requirements are met. – The designer uses the information requirements to develop cost, time, and feasibility estimates for alternative AIS solutions.© 2012 UMT Advanced Accounting Information Systems 27
  28. 28. PROTOTYPING • Four steps are involved in developing a prototype: – STEP ONE: Identify basic requirements – STEP TWO: Develop an initial prototype – STEP THREE: Repeated iterations – STEP FOUR: Use the system© 2012 UMT Advanced Accounting Information Systems 28
  29. 29. PROTOTYPING • The second step involves developing an initial prototype that meets the agreed-on requirements. – Emphasize speed and low cost rather than efficiency of operation. – The goal is to implement the prototype within a short time period.© 2012 UMT Advanced Accounting Information Systems 29
  30. 30. PROTOTYPING • Because of time constraints, some aspects are sacrificed. For example, at this point, you ignore: – Non-essential functions – System controls – Exception handling – Validation of input data – Processing speed – Efficiency considerations© 2012 UMT Advanced Accounting Information Systems 30
  31. 31. PROTOTYPING • Users must see and use tentative versions of: – Data entry display screens – Menus – Input prompts – Source documents • They must also: – Respond to prompts – Query the system – Judge response times – Issue commands© 2012 UMT Advanced Accounting Information Systems 31
  32. 32. PROTOTYPING • When the prototype is finished, the developer returns to the users and demonstrates the system. • Users are instructed to: – Experiment. – Comment on what they do and do not like.© 2012 UMT Advanced Accounting Information Systems 32
  33. 33. PROTOTYPING • Four steps are involved in developing a prototype: – STEP ONE: Identify basic requirements – STEP TWO: Develop an initial prototype – STEP THREE: Repeated iterations – STEP FOUR: Use the system© 2012 UMT Advanced Accounting Information Systems 33
  34. 34. PROTOTYPING • The third step involves repeated iterations of: – Users identifying changes. – Developers making the changes. – The system being turned back to users for next round. • This step continues until users are satisfied—usually 4 to 6 iterations.© 2012 UMT Advanced Accounting Information Systems 34
  35. 35. PROTOTYPING • Four steps are involved in developing a prototype: – STEP ONE: Identify basic requirements – STEP TWO: Develop an initial prototype – STEP THREE: Repeated iterations – STEP FOUR: Use the system© 2012 UMT Advanced Accounting Information Systems 35
  36. 36. PROTOTYPING • The final step involves using the system approved by the users. • An approved prototype is typically used in one of two ways.© 2012 UMT Advanced Accounting Information Systems 36
  37. 37. PROTOTYPING • Half of the prototypes are turned into fully functional systems referred to as operational prototypes. – To make them operational, the developer must: • Add needed controls. • Improve operational efficiency. • Provide backup and recovery. • Integrate the prototype with the systems with which it interfaces.© 2012 UMT Advanced Accounting Information Systems 37
  38. 38. PROTOTYPING • Changes may be necessary to allow the program to: – Accept real input. – Access real data files. – Process data. – Make necessary computations and calculations. – Produce real output.© 2012 UMT Advanced Accounting Information Systems 38
  39. 39. PROTOTYPING • When it’s not practical to modify the prototype to make a fully functional system, non-operational or throwaway prototypes can be used in several ways: – They may be discarded, and the systems requirements identified in the process of building them can be used to develop a new system. • If so, the SDLC is followed to develop the system, and the prototype is a model.© 2012 UMT Advanced Accounting Information Systems 39
  40. 40. PROTOTYPING – Alternately, they may be used as the initial prototype for an expanded system designed to meet needs of many users. – As a final alternative, if users and developers decide the system is unsalvageable, the prototype can be discarded completely.© 2012 UMT Advanced Accounting Information Systems 40
  41. 41. PROTOTYPING • When to use prototyping – Prototyping supports rather than replaces the SDLC. – It is appropriate when: • Users don’t fully understand their needs, or the needs change rapidly. • System requirements are difficult to define. • System inputs and outputs are not known. • The task to be performed is unstructured or semi-structured. • Designers are uncertain about what technology to use. • The system is crucial and needed quickly. • The risk of developing the wrong system is high.© 2012 UMT Advanced Accounting Information Systems 41
  42. 42. PROTOTYPING • The users’ reactions to the new system are important development considerations. • Many design strategies must be tested. • The design staff has little experience developing this type of system or application. • The system will be used infrequently so that processing efficiency is not crucial.© 2012 UMT Advanced Accounting Information Systems 42
  43. 43. PROTOTYPING • Good candidates for prototyping: – Decision support systems. – Executive information systems. – Expert systems. – Information retrieval systems. – Systems that involve experimentation and trial-and-error development. – Systems in which requirements evolve as the system is used.© 2012 UMT Advanced Accounting Information Systems 43
  44. 44. PROTOTYPING • Prototyping is usually inappropriate for: – Large or complex systems that: • Serve major organizational components; or • Cross numerous organizational boundaries. – Standard AIS components, such as: • Accounts receivable • Accounts payable • Inventory management© 2012 UMT Advanced Accounting Information Systems 44
  45. 45. PROTOTYPING • Advantages of prototyping: – Better definition of user needs • Because of intensive end-user involvement.© 2012 UMT Advanced Accounting Information Systems 45
  46. 46. PROTOTYPING • Advantages of prototyping: – Better definition of user needs – Higher user involvement and satisfaction© 2012 UMT Advanced Accounting Information Systems 46
  47. 47. PROTOTYPING • Advantages of prototyping: – Better definition of user needs – Higher user involvement and satisfaction – Faster development time • It may take days or weeks to get a prototype up vs. a year or more for a traditional system.© 2012 UMT Advanced Accounting Information Systems 47
  48. 48. PROTOTYPING • Advantages of prototyping: – Better definition of user needs – Higher user involvement and satisfaction – Faster development time – Fewer errors • Errors are detected early because the users experiment with each version. • It’s also easy to identify and terminate an infeasible AIS early.© 2012 UMT Advanced Accounting Information Systems 48
  49. 49. PROTOTYPING • Advantages of prototyping: – Better definition of user needs – Higher user involvement and satisfaction – Faster development time – Fewer errors – More opportunity for changes© 2012 UMT Advanced Accounting Information Systems 49
  50. 50. 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 • Some for 10–20% of the cost of traditional systems.© 2012 UMT Advanced Accounting Information Systems 50
  51. 51. PROTOTYPING • Disadvantages of prototyping: – Significant user time© 2012 UMT Advanced Accounting Information Systems 51
  52. 52. PROTOTYPING • Disadvantages of prototyping: – Significant user time – Less efficient use of system resources • Shortcuts in developing the system may result in: – Poor performance and reliability – High maintenance and support costs© 2012 UMT Advanced Accounting Information Systems 52
  53. 53. PROTOTYPING • Disadvantages of prototyping: – Significant user time – Less efficient use of system resources – Incomplete system development© 2012 UMT Advanced Accounting Information Systems 53
  54. 54. PROTOTYPING • Disadvantages of prototyping: – Significant user time – Less efficient use of system resources – Incomplete system development – Inadequately tested and documented systems • Who wants to do that stuff?© 2012 UMT Advanced Accounting Information Systems 54
  55. 55. PROTOTYPING • Disadvantages of prototyping: – Significant user time – Less efficient use of system resources – Incomplete system development – Inadequately tested and documented systems – Negative behavioral reactions • If the prototype is discarded, users may be upset about using it and losing it. • May also be dissatisfied if all their suggestions are not incorporated or if they have to go through too many iterations.© 2012 UMT Advanced Accounting Information Systems 55
  56. 56. PROTOTYPING • Disadvantages of prototyping: – Significant user time – Less efficient use of system resources – Incomplete system development – Inadequately tested and documented systems – Negative behavioral reactions – Never-ending development • If not managed properly, the development could get stuck in a terminal loop.© 2012 UMT Advanced Accounting Information Systems 56
  57. 57. Computer-Aided Software Engineering (CASE) Tools • Traditionally, software developers have created software to simplify the work of others, but not for themselves. • Computer-aided software (or systems) engineering (CASE) tools are an integrated package of computer-based tools that automate important aspects of the software development process. – Used to plan, analyze, design, program, and maintain an information system. – Also used to enhance efforts of managers, users, and programmers in understanding information needs.© 2012 UMT Advanced Accounting Information Systems 57
  58. 58. Computer-Aided Software Engineering (CASE) Tools • CASE tools do not replace skilled designers, but provide developers with effective support for all SDLC phases. • CASE software typically includes tools for: – Strategic planning – Project and system management – Database design – Screen and report layout – Automatic code generation© 2012 UMT Advanced Accounting Information Systems 58
  59. 59. Computer-Aided Software Engineering (CASE) Tools • Advantages of CASE technology: – Increased productivity • Can generate bug-free code from system specifications. • Can automate repetitive tasks.© 2012 UMT Advanced Accounting Information Systems 59
  60. 60. Computer-Aided Software Engineering (CASE) Tools • Advantages of CASE technology: – Increased productivity – Improved program quality • Can simplify enforcement of structured development standards, which: – Improves quality of development. – Reduces threat of serious design errors. • Can check internal accuracy of design and detect inconsistencies.© 2012 UMT Advanced Accounting Information Systems 60
  61. 61. Computer-Aided Software Engineering (CASE) Tools • Advantages of CASE technology: – Increased productivity – Improved program quality – Cost savings • Cost savings of up to 80–90% are possible.© 2012 UMT Advanced Accounting Information Systems 61
  62. 62. Computer-Aided Software Engineering (CASE) Tools • Advantages of CASE technology: – Increased productivity – Improved program quality – Cost savings – Improved control procedures • Encourages development early in the design process of: – System controls – Security measures – System auditability – Error handling procedures© 2012 UMT Advanced Accounting Information Systems 62
  63. 63. Computer-Aided Software Engineering (CASE) Tools • Advantages of CASE technology: – Increased productivity – Improved program quality – Cost savings – Improved control procedures – Simplified documentation Automatically documents as the system development progresses.© 2012 UMT Advanced Accounting Information Systems 63
  64. 64. Computer-Aided Software Engineering (CASE) Tools • Problems with CASE technology: – Incompatibility • Some tools don’t interact effectively with some systems.© 2012 UMT Advanced Accounting Information Systems 64
  65. 65. Computer-Aided Software Engineering (CASE) Tools • Problems with CASE technology: – Incompatibility – Cost • Some packages > $360,000.© 2012 UMT Advanced Accounting Information Systems 65
  66. 66. Computer-Aided Software Engineering (CASE) Tools • Problems with CASE technology: – Incompatibility – Cost – Unmet expectations • Only 37% of CIOs believe they achieved expected benefits.© 2012 UMT Advanced Accounting Information Systems 66
  67. 67. SUMMARY AND CONCLUSIONS • You’ve learned: – What reengineering processes entail and when they are appropriate. – How prototypes are used to develop an AIS and when it is advantageous to do so. – What computer-aided software engineering is and how it’s used in systems development.© 2012 UMT Advanced Accounting Information Systems 67

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