Information system analysis and design Dr. Dina Tbaishat

Recap Last lecture we looked at system analysis in more detail, including the main activities that take place in this process We also discussed the SSM proposed by Checkland, and introduced rich pictures Today we shall introduce root definitions as tools to help in problem definition and continue with SSM steps

Third Step: CATWOE and Root definitions To construct a root definition, mnemonic CATWOE is used where the letters represent important aspects of the systems that has to be considered, from the rich picture you should be able to identify: Customers (victims or beneficiaries?) Actions (who carries out the processes associated with transformation? Who is doing something?)

Transformation (what is happening?) World view (what are the assumptions?) Owners (who can stop the system?) Environment (what are the conditions in which the system is operating? What are the external constraints / opportunities?)

Now we can obtain one or more root definitions, for example: “This system is operated for (C) by (A) and involves (T), in the hope/assumption of (W). It is subject to (E) and can be stopped by (O) at any time” We shall now look at an example of a hospital from three perspectives: the doctor, the patient and the administrator (Avison, 2006)

Patient’s view Client: Me Actor: The doctor Transformation: Treatment Worldview: I’ve paid my taxes so I’m entitled to it Owner: The system, or maybe, the taxpayer Environment: The hospital A hospital is a place that I go to get treated by a doctor, I’m entitled because I’m a taxpayer, the system is there to make sure taxpayers get the treatment they need

Doctor’s view Client: Patients Actor: Me Transformation: Treatment (probably by specialized equipment, nursing care) Worldview: Treat as many people as possible within a working week Owner: Hospital administrators Environment: My works vs. my private life

A hospital is a system designed to enable me to treat as many patients as possible with the aid of specialized equipments and nursing care. Organizational decisions are made by the hospital administrators (who ought to try treating patients without the proper facilities) against a background of NHS politics and my vision of a profitable private practice and regular weekends with my family

Administrator’s view Client: Doctors Actor: Me Transformation: Enable Dr.s reduce waiting lists Worldview: Create bigger hospital within budget Owner: The government department of health Environment: Politics An institution in which Dr.s (and less expensive staff) are enabled by administrators to provide a service to avoid long waiting lists. Ultimate responsibility rests with government and the environment is political

Fourth Step: Conceptual models Trying to structure debate on what system is for – or might be for? Example 1: is a student assessment system: a system of appraisal for the teacher? a system of ‘grading’ students? an integral part of learning for students? something useful for future employers to assess competencies? Example 2: are prisons for rehabilitation or for the protection of society?

Rest of SSM steps Comparison of models with the real world Consideration of desired changes Action taken

References Sommerville, I. (2001). Software Engineering. UK: Addison Wesley Kendall, K. E., & Kendall, J. E. (2002). Systems analysis and design. USA: Pearson Education Avison, D. & Fitzgerald, G. (2006). Information Systems Development: Methodologies, Techniques and Tools. 4th edition. Maidenhead (Great Britain): McGraw-Hill Education Monk A., and Howard, S. (1998). The rich picture: a tool for reasoning about work context. Interactions (March-April)