Week 4 (2) 2008 IS33 ISD - SSM 1

COMP3470 IS33 People-Centred Information Systems DevelopmentWeek 4 : Lecture 2

ISD Approaches:Soft Systems Methodology (SSM)

School of ComputingFACULTY OF Engineering

IS33 ISD - SSM 2Week 4 (2) 2008

The General Systems Theory It has widespread influence in IS Characteristics of a system:

Has a boundary and everything else is its environment

Input-process-output (input and output are the interactions with the environment)

Consists of a set of interrelated elements (or subsystems)

See organisations as ‘open’ systems Hard versus soft approaches

IS33 ISD - SSM 3Week 4 (2) 2008

Checkland’s SSM Mode 1 (fig 24.1 in Avison & Fitzgerald)

A 7-stage methodologyStill the version most commonly referred to

Mode 2 (fig 24.3 in Avison & Fitzgerald)Sees Mode 1 as just one option of a more

general approachHas 2 strands of enquiry – ‘logic-driven

stream’ and ‘cultural stream’More of a framework of ideas for

exploration rather than a methodology

IS33 ISD - SSM 4Week 4 (2) 2008

SSM Mode 1 Finding out about the problem situation (1 &

2) Use Rich Picture

Analyst at work (3 & 4) “A root definition is a concise, tightly constructed

description of a human activity system which states what the system is”

Use CATWOE criteria <can be taken from different perspectives – need to specify>

Decision time (5 & 6) Action (7)

IS33 ISD - SSM 5Week 4 (2) 2008

CATWOE C = Client /customer (the beneficiary or

victim) A = Actor (the change agent, who carries out

the transformation process) T = Transformation (the core of the root

definition – i.e. the ‘what’ to be changed) W = Weltanschauung (the world view, the

assumption taken for granted in the context) O = Owner (the sponsor or controller) E = Environment (the wider system of which

the problem situation is a part)

In Avison & Fitzgerald pp. 162-166

IS33 ISD - SSM 6Week 4 (2) 2008

An exercise

Problem situation:

SOC cannot seem to get good quality student feedback on its teaching

Apply Rich Picture and CATWOE to understand the problem situation

IS33 ISD - SSM 7Week 4 (2) 2008

Pros & Cons of SSM

IS33 ISD - SSM 8Week 4 (2) 2008

For next lecture

Read Montealegre R & Keil M, De-escalating Information Technology Projects: Lessons from the Denver International Airport, MIS Quarterly, Vol 24, No. 3, Sept 2000, pp.417-447 (available via Library’s electronic journals).