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UFCE8V-20-3 Information Systems Development SHAPE Hong Kong 2010/11. Lecture 4 : Soft Systems Thinking & Practice. Human Activity Systems (HAS). All human activity systems (HAS) are social systems. All social systems are open systems. They consist of people and their activities.
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UFCE8V-20-3Information Systems DevelopmentSHAPE Hong Kong 2010/11 Lecture 4 : Soft Systems Thinking & Practice
Human Activity Systems (HAS) • All human activity systems (HAS) are social systems. • All social systems are open systems. • They consist of people and their activities. • 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. • Hence human activity systems are inherently complex and open to different interpretations or “readings”. • 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. UFCE8V-20-3 Information Systems Development SHAPE 2010/11
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) UFCE8V-20-3 Information Systems Development SHAPE 2010/11
Mechanism v Teleology • Teleology – the study of goal-seeking or goal-directed behaviour. • In mechanistic thinking behaviour is explained by what caused it and its effects. Causal chains as in A->B->C->D... • In teleological thinking behaviour is explained by what produced it or by what it is intended to produce. • 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. UFCE8V-20-3 Information Systems Development SHAPE 2010/11
A human activity system view of problem, methodology, method & success A PROBLEMis: • a situation in need of improvement • a condition in need of change • an unrealized goal, aim, intention or desire • a project or task • a unsatisfied need • a barrier, a limitation; an obstacle to be overcome • a constructive purpose • an imbalance; disharmony; disorder; disunity UFCE8V-20-3 Information Systems Development SHAPE 2010/11
A human activity system view of problem, methodology, method & success (2) METHODOLOGYis: • A systematic sequence of steps, stages, or events • An outline plan for managing problems and goals • An "excursion" (Gordon) • A tried and tested pattern of activities • The path of problem-solving journey • A means of organizing effort and expense • A clarification of purpose and activity UFCE8V-20-3 Information Systems Development SHAPE 2010/11
A human activity system view of problem, methodology, method & success (3) METHODSare: • Ways and means; techniques; "how-tos" • Problem-solving tools • Strategies; tricks; 'trade secrets' • Sub-procedures; mini-processes UFCE8V-20-3 Information Systems Development SHAPE 2010/11
A human activity system view of problem, methodology, method & success (4) SUCCESS is: • Satisfying one's needs • Solving a problem; completing a project • Positive feedback or evaluation • Realization of achievement • Reaching one's goals UFCE8V-20-3 Information Systems Development SHAPE 2010/11
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 - • Checkland’s “Soft Systems Methodology” (SSM) • Mumford’s“Effective Technical & Human Implementation of Computer-Based Systems” (ETHICS) • Mason and Mitroff’s “Strategic Assumption Surfacing and Testing” (SAST) • Ulrich’s “Critical Systems Heuristics” (CSH) UFCE8V-20-3 Information Systems Development SHAPE 2010/11
Checkland’s Soft Systems Methodology (SSM) Four underlying principles. Learning, culture, participation and the “two modes of thought”. • Learning– SSM articulates a process of enquiry, it is a learning system that leads to purposeful action in a continuous cycle. • Culture– systemic feasibility, desirability and relevance. • Participation – given the variety of perceptions, it is not only desirable but necessary. • Two modes of thought– abstract and ideal systems thinking. UFCE8V-20-3 Information Systems Development SHAPE 2010/11
SSM’s two streams of enquiry UFCE8V-20-3 Information Systems Development SHAPE 2010/11
SSM – the seven stages UFCE8V-20-3 Information Systems Development SHAPE 2010/11
SSM Stages 1-2 The 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). UFCE8V-20-3 Information Systems Development SHAPE 2010/11
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: • C: customer (people affected by the system, beneficiaries or victims); • A: actor (people participating in the system); • T: transformation (the core of the root definition – the transformation carried out by the system); • W: Weltanschauung (“world view”); • O: ownership (the person(s) with the authority to decide on the future of the system); • E: environment (the wider system). • 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.
SSM stages 4-7 • Stage fourEach root definition will result in a conceptual model. The conceptual model identifies the minimum necessary activities for that 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. • Stages five and sixThe 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 sevenRecommendations 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. UFCE8V-20-3 Information Systems Development SHAPE 2010/11
Example “Rich Picture” UFCE8V-20-3 Information Systems Development SHAPE 2010/11
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 UFCE8V-20-3 Information Systems Development SHAPE 2010/11