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UFCE8V-20-3 Information Systems Development 3 (SHAPE HK) Lecture 17 Soft Systems Thinking

UFCE8V-20-3 Information Systems Development 3 (SHAPE HK) Lecture 17 Soft Systems Thinking

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Page 1: UFCE8V-20-3 Information Systems Development 3 (SHAPE HK) Lecture 17 Soft Systems Thinking

UFCE8V-20-3 Information Systems Development 3 (SHAPE HK)

Lecture 17Soft Systems Thinking

Page 2: UFCE8V-20-3 Information Systems Development 3 (SHAPE HK) Lecture 17 Soft Systems Thinking

Human Activity Systems (HAS)o All human activity systems (HAS) are social systems. o All social systems are open systems.o They consist of people and their activities.o Activities involve intentional and meaningful actions

carried out by individuals and groups who ascribe purposes to their own actions and to the actions of others.

o Hence human activity systems are inherently complex and open to different interpretations or “readings”.

o And why the means-end (hard systems) ideas & techniques derived from a positivist tradition are (by themselves) inadequate for problem solving in this human activity domain.

Page 3: UFCE8V-20-3 Information Systems Development 3 (SHAPE HK) Lecture 17 Soft Systems Thinking

A systems Typology

Five classes of system which make up a systems map of the universe. We may– investigate, describe, learn from, natural systems – create and use designed systems – seek to ‘engineer’ human activity systems (P Checkland)

Page 4: UFCE8V-20-3 Information Systems Development 3 (SHAPE HK) Lecture 17 Soft Systems Thinking

Mechanism v Teleologyo Teleology – the study of goal-seeking or goal-directed

behaviour.o In mechanistic thinking behaviour is explained by what

caused it and its effects. “Causal chains” as in A->B->C->D...

o In teleological thinking behaviour is explained by what produced it or by what it is intended to produce.

o Study of the functions, goals and purposes of individual and groups yields a greater chance to understand and improve performance within human activity systems than the study of mechanism (on its own) can.

Page 5: UFCE8V-20-3 Information Systems Development 3 (SHAPE HK) Lecture 17 Soft Systems Thinking

A human activity system view of problem, methodology, method & success

A PROBLEM is:o a situation in need of improvement o a condition in need of changeo an unrealized goal, aim, intention or desireo a project or tasko a unsatisfied needo a barrier, a limitation; an obstacle to be overcomeo a constructive purposeo an imbalance; disharmony; disorder; disunity

Page 6: UFCE8V-20-3 Information Systems Development 3 (SHAPE HK) Lecture 17 Soft Systems Thinking

METHODOLOGY is:o A systematic sequence of steps, stages, or eventso An outline plan for managing problems and goalso An "excursion" (Gordon)o A tried and tested pattern of activities o The path of problem-solving journeyo A means of organizing effort and expenseo A clarification of purpose and activity

A human activity system view of problem, methodology, method & success (2)

Page 7: UFCE8V-20-3 Information Systems Development 3 (SHAPE HK) Lecture 17 Soft Systems Thinking

METHODS are:o Ways and means; techniques; "how-tos"o Problem-solving toolso Strategies; tricks; 'trade secrets'o Sub-procedures; mini-processes

A human activity system view of problem, methodology, method & success (3)

Page 8: UFCE8V-20-3 Information Systems Development 3 (SHAPE HK) Lecture 17 Soft Systems Thinking

SUCCESS is:o Satisfying one's needso Solving a problem; completing a projecto Positive feedback or evaluationo Realization of achievemento Reaching one's goals

A human activity system view of problem, methodology, method & success (4)

Page 9: UFCE8V-20-3 Information Systems Development 3 (SHAPE HK) Lecture 17 Soft Systems Thinking

Soft systems methodologies

Specifically developed to be used in messy or ill-structured situations. That is, situations where there may not be a clear view of what constitutes the problem, or for that matter, what action should be taken to overcome the difficulties being expressed.

Examples of soft systems methodologies include -o Checkland’s “Soft Systems Methodology” (SSM)o Mumford’s “

Effective Technical & Human Implementation of Computer-Based Systems” (ETHICS)

o Mason and Mitroff’s “Strategic Assumption Surfacing and Testing” (SAST)

o Ulrich’s “Critical Systems Heuristics” (CSH)

Page 10: UFCE8V-20-3 Information Systems Development 3 (SHAPE HK) Lecture 17 Soft Systems Thinking

Checkland’s Soft Systems Methodology (SSM)

Four underlying principles. Learning, culture, participation and the “two modes of thought”.

o Learning – SSM articulates a process of enquiry, it is a learning system that leads to purposeful action in a continuous cycle.

o Culture – systemic feasibility, desirability and relevance. o Participation – given the variety of perceptions, it is not

only desirable but necessary.o Two modes of thought – abstract and ideal systems

thinking.

Page 11: UFCE8V-20-3 Information Systems Development 3 (SHAPE HK) Lecture 17 Soft Systems Thinking

SSM’s two streams of enquiry

Page 12: UFCE8V-20-3 Information Systems Development 3 (SHAPE HK) Lecture 17 Soft Systems Thinking

SSM – the seven stages

Page 13: UFCE8V-20-3 Information Systems Development 3 (SHAPE HK) Lecture 17 Soft Systems Thinking

SSM Stages 1-2The problem situation can be expressed as a “rich picture”. The idea is to represent pictorially all the relevant information and relationships. This is simply to aid the modeller or consultant to gain an understanding of the situation. The rich picture will reveal one or more Human Activity Systems (HAS).

Page 14: UFCE8V-20-3 Information Systems Development 3 (SHAPE HK) Lecture 17 Soft Systems Thinking

SSM stage 3“Root definitions” are constructed for the relevant HAS identified in

stages one and two. The root definition should encompass the emergent properties of the system in question. To define the emergent properties one needs to consider the mnemonic CATWOE:

o C: customer (people affected by the system, beneficiaries or victims);

o A: actor (people participating in the system); o T: transformation (the core of the root definition – the

transformation carried out by the system); o W: Weltanschauung (“world view”); o O: ownership (the person(s) with the authority to decide on the

future of the system); o E: environment (the wider system). o The CATWOE mnemonic can be used as a checklist to ensure that

the root definition is complete. Alternatively, the root definition can be formulated from the components of the CATWOE mnemonic. Either way, the root definition will be a short paragraph which will contain all the necessary information to describe the system. Several root definitions can be constructed for each of the relevant HAS identified. Each root definition will encompass a different Weltanschauung.

Page 15: UFCE8V-20-3 Information Systems Development 3 (SHAPE HK) Lecture 17 Soft Systems Thinking

Each root definition will result in a conceptual model.

The conceptual model identifies the minimum necessary activities for that Human Activity System(HAS).

In addition, it represents the relationships between the activities.

The conceptual model must be derived from the root definition alone. It is an intellectual model and must not be clouded by knowledge of the “real” world.

All of the elements of the CATWOE mnemonic must be included somewhere in the conceptual model, otherwise the conceptual model is incomplete. It should not be possible to take out words from the root definition without affecting the conceptual model.

[** Note that ‘conceptual models’ here are very different to conceptual (ER) models]

SSM stage 4

Page 16: UFCE8V-20-3 Information Systems Development 3 (SHAPE HK) Lecture 17 Soft Systems Thinking

Stages five and six The conceptual model identifies which activities need to be included in that particular HAS. It is not concerned with how these activities will be carried out. The conceptual model will be compared with the real world to highlight possible changes in the real world. It may be that activities in the conceptual model do not exist in the real world. This would then be a recommendation for change. Differences between the two must never result in a change to the conceptual model. The conceptual model, if constructed correctly, encompasses all the activities necessary for the emergent properties of the system. Removal of activities from the conceptual model would result in those emergent properties being lost. Conversely, it may be the case that activities appear in the real world that do not fit into the conceptual model. These activities are either unnecessary, or are included in the conceptual model in a different form.

Stage seven Recommendations for change will be implemented. It is important to appreciate that once these changes have been implemented, the problem situation will be modified. In other words, the process is cyclical.

SSM stages 5-7

Page 17: UFCE8V-20-3 Information Systems Development 3 (SHAPE HK) Lecture 17 Soft Systems Thinking

Example “Rich Picture”

Page 18: UFCE8V-20-3 Information Systems Development 3 (SHAPE HK) Lecture 17 Soft Systems Thinking

Example “Root Definition”“A householder-owned and manned system to paint a garden

fence, by conventional hand painting, in keeping with the overall decoration scheme of the property, in order to enhance the visual appearance of the property & the lifetime of the fence”

• Customer = householder & family• Actor = householder• Transformation = unpainted fence painted fence

meeting criterion in the definition• Weltanschauung = painting can enhance the appearance &

longevity of fence• Owner = householder• Environment = rest of house & garden, neighbours