What is a METHODOLOGY The term is not well defined either in the litterature or by practitioners, but here is some definitions ” a methodology is a collection of procedures, techniques, tools and documentation aids, supported by a philosophy, which will help the systems developers in their efforts to implement a new information system” (Avison and Fitzgerald) ”a set of principels of method which in any particular situation has to be reduced to a method uniquely suited to that particular situation ” (Checkland) What does a methodology consist of ” A methodology will consist of phases, themselves consisting of sub-phases, which will guide the system developers in their choice of techniques that might be appropriate at each stage of the project and also help manage, control and evaluate system projects” Avison and Fitzgerald It is more than a collection of tools and techniques It should specify: - Stages into which a project should be broken down - Tasks for each stage - Outputs produced(for each task and stage) - Support tools to use - How project is to be managed and controlled All encompassed in a philosphy The objectives of a metholodology are to: Record accurately the requirements for an information system. Provide a systematic method of development in such a way that progress can be effectively monitored. Provide an information system within an appropriate time limit and an acceptable cost. Produce a system which is well documented and easy to maintain. Identify any necessary changes in the development process Provide a usable system Why a methodology A better end product - use of any methodology better than none at all. - aim to improve - acceptability to the user - cohesiveness - standards for dokumentation - maintability A better development process A standardised process Remember that methodologies have limitations. - Generel purpose or specific environment - May cover one or more aspects of the development system - If results can’t be reproduced what is wrong? The methodology or the process - - - Comparison of methodologies. Why compare??????? Academic reason: to understand the nature of methodologies and to improve them. - discover real differences between them. - discover compability between methods. - discover weeknesses in methods - uncover false assumptions about methodes. Practical reason: to aid selection for project/group of projects/organisation. Problems with comparison ( different methodologies and the phases they cover) Terminological confusion Methodologies are moving targets. Avison and Fitzgeralds framework for comparison Philosophy ( principels) a) Paradigm ( a specific way of thinking about the problems). b) Objectives (the purpose of the system) c) Domain ( make a top down analysis of the organisation, find the strategic requirements and make sure, that the system solve these fundamental requirements. Model (wiew of the world) Techniques and tools Scope (stages of lifecycles – how many phases is covered) Output Practice - Background - User base - Participants Product.