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Management Information Systems. Chapter 10. Information Systems Development. This Could Happen to You. Dee wanted to develop a blog for communication Focused goal Short time frame Was successful because system was simple Single contributor No user training RFID at DSI more sophisticated
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Management Information Systems Chapter 10 Information Systems Development
This Could Happen to You • Dee wanted to develop a blog for communication • Focused goal • Short time frame • Was successful because system was simple • Single contributor • No user training • RFID at DSI more sophisticated • Vendors would need to place RFID chips • Computer program would be needed to process data
Study Questions • Q1. What is systems development? • Q2. Why is systems development difficult and risky? • Q3. What are the five phases of the systems development life cycle? • Q4. How is systems definition accomplished? • Q5. What is the user’s role in the requirements phase? • Q6. How are the five components designed? • Q7. How is an information system implemented? • Q8. What are the tasks for systems maintenance? • Q9. What are the problems with SDLC?
Q1. Systems Development • Systems analysis and design • Process of creating and maintaining information systems • Development involves all five components • Requires more than programming or technical expertise • Human relation skills • Business knowledge • Understanding of group dynamics • Information systems are never off-the-shelf • Must be adapted to fit needs of business and people
MIS in Use: Thinking Big about Systems Development • Large scale corporate information systems are more complex • Need to ensure all employees are working toward same goals • Must develop system that will function consistently in different languages • May need to store information on worldwide use of product and the relevant laws • Most information systems are process-design oriented • Must be carefully planned and executed
Q2. Major Development Challenges • Difficulty of determining requirements • Requirements change as system develops • Scheduling and budgeting difficult to estimate • Change as scope changes • Technology changes • Diseconomies of scale • Brook’s Law
Q3. Systems Development Processes • Methodologies: • Systems development life cycle (SDLC) • Rapid application development (RAD) • Object-oriented systems development (OOD) • Extreme programming (XP) • No single process works in all situations • Different requirements • Some systems wholly automated, others not • Use augmentation system to fill gaps
SDLC • Classical process with five phases: • Systems definition • Management’s statement defines new system • Requirements analysis • Identify features and functions • Component design • Based on approved user requirements • Implementation • Implement, test, and install new system • System maintenance • Repair, add new features, maintain
Q4. Systems Definition (1) • Define goals and purpose for new system • Must facilitate organization’s competitive strategy • Supports business processes • Improves decision making • Determine project’s scope • May be delineated by users, processes, or facilities • Assess feasibility of project • Cost • Schedule • Technical feasibility • Organizational feasibility
Systems Definition (2) • If deemed feasible, project team created from IT personnel and users • Managers • Systems analysts • Programmers and software testers • Users
Ethics Guide: Estimation Ethics • Buy-ins • Companies agree to produce products for less than it knows will be required • “Time and materials” contracts • Fixed-cost contracts • In-house projects are often started with buy-ins • Projects started with hopes of more money later • Team members may disagree about costs • Not all costs may have been included in estimate • Also may have buy-in on schedule
Q5. Requirements Analysis Phase • Determine and document features and functions • Interview users • Document requirements • Examine existing system • Review reports, forms, queries, application features • Security and controls • Approve requirements • Less expensive to change system in this phase
Q6. Designing Components • Develop and evaluate alternatives • Accurate requirements critical • Hardware design determined by project team • Software design depends on source • Off-the-shelf • Off-the-shelf with alterations • Custom-developed programs • Data model converted to database design • Procedures designed for BI system • Job descriptions created for users and operations personnel
Q7. Information System Implementation • System must be built • Components constructed independently • Document and review • System testing • Individual components tested • System integrated and tested • Users must be converted to new system
Systems Testing • Test plan • Sequences of actions that users take when employing system • Both normal and incorrect actions should be considered • Labor intensive • Product quality assurance (PQA) • Testing specialists • Beta testing • Future system users try out system on their own
System Conversion (1) • Converting business activity from old system to new • Pilot installation • Organization implements entire system on single, limited unit • If systems fails, it only affects limited boundary • Reduces exposure • Phased installation • New system installed in phases • Tested after each phase • Continues until installed at entire organization • Can’t be used in tightly integrated systems
System Conversion (2) • Parallel installation • New system runs in parallel with old system during testing • Expensive and time consuming • Data must be entered twice • Provides easy fallback position • Plunge installation • Direct installation • Install new system and discontinue old • There is no backup position
Q8. Systems Maintenance • Fixing or adapting system • Need method to track system failures and enhancements • Corrections usually prioritized based on severity • Enhancements usually prioritized based on business decision • Must generate reasonable rate of return • Decision to restart systems development process
Q9. Problems With SDLC • SDLC waterfall • Phases are not supposed to be repeated • Often teams have need to repeat requirements and/or design phases • Difficulty in documenting requirements • Analysis paralysis or uncertain requirements • Scheduling and budget difficulties • Multiyear projects difficult to properly schedule • Estimations on labor often produce insufficient budgets
Guide: The Real Estimation Process • Estimating is just theory • Project managers sum up estimates and take to management • Management then negotiates the schedule and budget • Every change will negatively impact the project • Start with optimistic schedules and end up with late projects
How Does the Knowledge from This Chapter Help You at DSI? • You can now give a summary of the phases of SDLC • Describe tasks more specifically • Create a realistic schedule