BT2103 Developing Small Systems for Business

1. BT2103Developing Small Systemsfor Business Lecture 3 Planning and Development Methodologies

2. Definition • Reasons for new system • Traditional Systems Development • Lifecycle • Analysis Techniques • The role of the systems analyst • CSF’s and KPI’s • Types of methodology • SSADM, SSM and RAD (Pro’s and Con’s) • Alternative solutions (Pro’s and Con’s) Contents

3. From the Greek “Study of Methods” A methodology can be defined as: “a collection of procedures, techniques, tools and documentation aids which help the systems developers in their aim to implement a new information system” Avison and Fitzgerald (1996) Definition

4. Current system can’t cope • Time saving • Cost saving • Information for decisions • Competitive advantage for organisation • Competitive service for customers • New technology image • New legal requirements Reasons for new system

5. 5 Stage process: • Investigation • Analysis • Design • Implementation • Maintenance Traditional Systems Development Lifecycle Investigation Maintenance Analysis Implementation Design

6. Detect business problem/opportunity • Conduct feasibility study • Cost vs. Benefits • Most costs are tangible, but most benefits are not • Develop project plan • Obtain approval Investigation

7. Information needs of end users. • Current systems (computer or otherwise) • Develop functional requirements Analysis

8. Procedure Narratives • Data Flow Diagrams • Entity Relationship Models Analysis Techniques

9. Describes in basic steps exactly what happens in a process • Good for recording processes in detail • But • Can be too detailed • Does not show any dynamic relationships Procedure Narratives

10. Shows relationships between entities and processes both inside and outside the system • Can have several layers of detail • Mainly used for ‘hard’ methodologies Data Flow Diagrams

11. AKA Logical Data Models • Show underlying meaning to DFD’s • Logical Data Structure • Diagram and descriptions • Entity Life History • Documents stages of entity development Entity Relationship Diagrams

12. Specify: • Hardware • Software • Users • Data resources • Information products (reports etc.) Design

13. Acquire components • Convert data • Test system • Train users • Make new system operational • Different methods: • Parallel, Phased, Cut Off • Pro’s and Con’s Implementation

14. Review system’s functions • Gain user’s feedback • Monitor • Evaluate • Modify where necessary Maintenance

15. Investigation of the existing system • Managing the feasibility study • Conceptual design (logical) • Overseeing the testing • Coordinating the implementation • Evaluation of the system performance • Must be a good communicator The role of The Systems Analyst

16. Critical Success Factors: • Operational goals • Hospital – We need to use our Operating Theatres more effectively • Key Performance Indicators: • Measurement of success • Hospital – Number of hours OT is idle - Number of operations performed - Are numbers enough? CSF’s and KPI’s

17. Types of Methodology Business problem/opportunity ETHICS SSM Exploration of problem Fully explore what is needed IE RAD SSADM Full design brief Design Build Implement

18. Expanded the 5 point list to 7 (version 4) • Feasibility • Investigation of current environment • Business system options • Definition of requirements • Technical system options • Logical design • Physical design SSADM

19. Benefits • Excellent where requirements are defined and structured • Disadvantages • Time consuming • Costly • Inflexible Benefits and Disadvantages

20. ‘An organised way of tackling a messy situation’ (Checkland and Scholes) • Developed to help with unstructured and poorly defined problems • Centres on individual’s experiences of the problem • Therefore, ‘right information’ rarely exists SSM

21. Situation considered problematic • Problem expressed • Definition of purposeful activity • Conceptual systems models • Comparison (model to real world) • Changes • Action to improve problem situation Stages in SSM (Real world) (Systems thinking) (Real world)

22. SDLC Problems

23. Prototyping (RAD) • Application Software Packages • End – User Development • Outsourcing Alternative Solutions

24. An experimental system, put together quickly for feedback from users • The prototype is a working version of all or part of the system • Users’ requirements are met by constant refining through iterative processes Prototyping (RAD)

25. Prototyping RAD Identify basic requirements Revise the prototype Use the prototype No Develop a working prototype Operational prototype User feedback positive? Yes

26. Viable alternative to some bespoke systems development • Off-the-shelf packages for more and more solutions • Implementation time and costs greatly reduced • May not meet all requirements Application Software Packages

27. Increasingly used in today’s organisations • Easier to define user requirements • Benefits: • Increase in user satisfaction / productivity • Disadvantages: • Documentation? • Managerial control? • Ownership End – User Development

28. The hiring of an external organisation • Benefits: • Reduces need for IS department • Accommodate fluctuating needs • Disadvantages: • Loss of control over: • Technology • Competitive advantage • Own IS function Outsourcing

29. The development of a system should be managed through the use of a suitable methodology • As many different development methodologies exist as there are systems • Alternative approaches such as EUD and outsourcing exist • The whole process should be managed by a systems analyst Conclusion