IMS3230 - Information Systems Development Practices

1. IMS3230 - Information Systems Development Practices Frameworks for comparing ISD methodologies Semester 2, 2005

2. References • Prescribed text: Avison, D.E. & Fitzgerald, G. (2003). Information Systems Development: Methodologies, Techniques and Tools. (3rd ed), McGraw-Hill, London. Chapters 25, 26, 27

3. Frame works for comparing and evaluating ISDMs • paradigms • frameworks • comparing methodologies • selecting a methodology

4. Frame works for comparing and evaluating ISDMs • paradigm: “the most fundamental set of assumptions adopted by a professional community that allows its members to share similar perceptions and engage in commonly shared practices” Klein and Hirschheim (1989) ontology: assumptions about the nature of the physical and social world epistemology: assumptions about knowledge and how to acquire it

5. Science vs systems paradigms The science paradigm: embodies scientific method reductionism, repeatability, refutation • reduce the complexity and variety of the real world, analysis and synthesis strategies, cause and effect relationships • knowledge is validated by the repetition of experiments producing the same results • knowledge is built up by hypotheses being refuted • suited to the world of natural phenomena Wood-Harper and Fitzgerald (1982): E.g. traditional approaches, data analysis, structured approaches

6. Science vs systems paradigms the systems paradigm: embodies a holistic approach • holistic: emergent properties • properties of systems: purpose, interaction of elements, openness, communication and control • understand system context • multiple viewpoints • suited to the social world Wood-Harper and Fitzgerald (1982): E.g. human activity system approaches (e.g.SSM), participative approaches (e.g. ETHICS)

7. Objectivist and subjectivist paradigms Klein and Hirschheim (1989) the objectivist paradigm • a realist ontology: reality is objectively given, exists independently of our perceptions of it there is one “correct” view which is discoverable • a positivist epistemology: explain observable phenomena by identifying causal relationships same methods are appropriate for the natural and the social worlds

8. Objectivist and subjectivist paradigms Klein and Hirschheim (1989) the subjectivist paradigm • a nominalist ontology: reality is subjectively constructed via our framework of values, beliefs and experiences there are different, valid viewpoints • an interpretivist epistemology: relativistic, questions the existence of “objective” knowledge we need to understand the way in which the world is interpreted

9. Objectivist and subjectivist paradigms implications for systems development methodologies: • system developers must conduct enquiry • system developers must intervene in the organisational social world • objectives of systems development • techniques and tools • role of systems developers

10. Frameworks • for describing the concept of a methodology e.g. the meta-model of Olle et al (1991) • for describing a specific methodology e.g. the system lifecycle • for comparing and / or evaluating methodologies e.g. feature analyses analyses of results of using methodologies

11. Frameworks for comparing • feature analyses: identify a set of desirable features determine whether specific methodologies have each feature attempt to evaluate to what extent features are present • problems with feature analyses: - determining the features - versions of methodologies - problems of terminology - subjectivity of analysis - subjectivity of evaluation

12. Frameworks for comparing • a generalised framework of features for comparison: Avison and Fitzgerald (1995) Chap 7 • features: - philosophy - model - techniques and tools - scope - outputs - practice - product There are other important features: e.g.

13. Selecting an ISD methodology • contingency approaches: there is no best methodology selection depends on the project context: - the nature of the problems being addressed - the nature of the applications - the nature of the organisation and its culture E.g. Burns and Dennis (1985): • project uncertainty (high / low) • project complexity (high / low) e.g. ill-structuredness of problem situation, system size, the user component, the developer component the state of flux of the system requirements

14. Selecting an ISD methodology NIMSAD (Jayaratna 1994): evaluate using three criteria problem situation (context): • how does the methodology help understand the problem situation? problem solver (methodology user): • what are the values, skills, experiences etc. of the user? • how do the users’ values relate to those of the methodology? problem solving process (methodology): • how does the methodology assist in defining, documenting problems and designing solutions? NIMSAD has been applied to SSM, ETHICS, and Structured Analysis

15. Adopting an ISD methodology • a wide range of system development methodologies exists • no single system development methodology will suit all projects and organisations solutions to this problem: • construct a tool kit of methods, techniques and tools to select from • build a blended methodology (e.g. Multiview) • build a methodology in-house tailored to the needs of the organisation

16. The tool kit approach • models used within different systems development methodologies are tools available to the analyst • select according to the needs of the situation disadvantages • no integrating philosophy: just a set of methods, tools and techniques • idiosyncratic, unmaintainable systems • selection of appropriate techniques etc. requires skill and experience • difficulty in training new systems analysts • lack of standardisation

17. Build a blended methodology “blend” the best of existing approaches: (e.g. Multiview) • difficulty of merging incompatible philosophies • difficulty of integrating outputs produced using one approach with those of another approach • analysts need to understand and be experienced in using several different approaches

18. Tailored, in-house methodology develop a “tailored” methodology based on an existing approach: • underlying philosophy provides rationale for products and processes • techniques and tools are integrated • customised to fit in with the organisational environment

19. Adopting an ISD methodology the need for an ISD methodology • a “better” end product: acceptable? available? maintainable? meets requirements? etc...... • a “better” development process: project control? productivity? fewer resources used? • a standardised process: a common organisational approach? or flexibility? creativity? • how are systems development methodologies really selected?