IMS 5006 — Information Systems Development Practices Frameworks

IMS 5006 - Information Systems Development Practices Frameworks for comparing ISD methodologies 1

Frame works for comparing and evaluating ISDMs § paradigms § frameworks § comparing methodologies § selecting a methodology 2

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 3

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 4

Science vs systems paradigms the systems paradigm: embodies a holistic approach § § holistic: emergent properties § § § understand system context properties of systems: purpose, interaction of elements, openness, communication and control 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) 5

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 6

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 7

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 8

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 of results of using methodologies 9

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 10

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. 11

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 12

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 13

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 14

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 15

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 be experienced in using several different approaches 16

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 17

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? 18

References § Prescribed text: Avison, D. E. & Fitzgerald, G. (2003). Information Systems Development: Methodologies, Techniques and Tools. (3 rd ed), Mc. Graw-Hill, London. Chapters 25, 26, 27 19