department of computer science seminar 11: critical systemssme/systemsthinking/slides/11... · 1...
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 3
Seminar 11:Critical Systems
!How Systems ChangeÄPanarchy Theory: origins and applications
!Principle of ComplementarityÄHard vs Soft Systems
!Soft System Methodology
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 4
Ecology at multiple scales
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 5
Boreal Forest
Image Source: Gundersson & Holling (2002). Panarchy
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 6
Everglades
Image Source: Gundersson & Holling (2002). Panarchy
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 7
Time and Scale
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 8Image source: http://www.climas.arizona.edu/blog/climate-and-floods-southwest
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 9
Social “rule sets”
Image Source: Gundersson & Holling (2002). Panarchy
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 10
r-K Selection Theory
r species (opportunistic): High growth rate, Many offspring, Low survival
K species (equilibrium): Low growth rate, Few offspring, High survival
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 11
Growth of Complexity
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 12
Panarchy Theory
Image Source: Gundersson & Holling (2002). Panarchy
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 13
Multi-level change
Image Source: Gundersson & Holling (2002). Panarchy
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 14See: http://www.liberatingstructures.com/32-panarchy/
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 15Source: https://www.pnas.org/content/110/7/E549
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 16
Adaptive Cycle Examples! Physical Systems (e.g. tectonic plates, sand piles)
Ä Little scope for evolution/innovationÄ Tend to repeat cycles rather than evolve (organized criticality)
! Ecosystems with unpredictable conditionsÄ Highly adaptive responses to opportunityÄ Tend to oscillate between α and r phases
! Ecosystems & human systems with predictable conditionsÄ Can have significant internal regulationÄ Tend to exhibit the full boom and bust cycle
! Biological entitiesÄ System variables remain in homeostatic equilibriumÄ Adaptive cycle operates at higher scale (community/ecosystem)
! Human systems with foresightÄ Predictive capacity used to stabilize variables and exploit opportunityÄ Adaptive cycle operates at lower sale (individuals/entrepreneurs)
Holling, C. S. (2001). Understanding the Complexity of Economic, Ecological, and Social Systems. Ecosystems, 4(5), 390–405.
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 17
Observes
Compares
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 21
Relativism
TimeTime
The agricultural revolution Transistor switching
Food
pro
duct
ion
Cur
rent
4000 years10-9 sec
!Truth is relative to many thingsÄThe meanings of the words we use
Ø E.g. law of gravity depends on correct understanding of “mass”, “distance”, “force” etc
ÄThe assumptions we make about contextØ E.g. law of gravity not applicable at subatomic level, or near the speed of lightØ E.g. Change expressed on different spatial and temporal scales:
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 22
Relativism is everywhere
!Truth often depends on the observerÄ“Emergent properties of a system are not predictable from studying the parts”
Ø Whose ability to predict are we talking about?
Ä“Purpose of a system is a property of the relationship between system & environment”
Ø What is the purpose of: General Motors? A University? A birthday party?
!Weltanshaungen (≈ “worldviews”)ÄThe set of categories we use for understanding the worldÄThe language we develop for describing what we observe
!Ethno-centrism (or ego-centrism)ÄThe tendency to assume one’s own category system is superior
Ø E.g. “In the land of the blind, the one-eyed man is king”Ø But what use would visually-oriented descriptions be in this land?
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 23
Principle of Complementarity
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 24
The principle of complementarity
!Raw observation is too detailedÄWe systematically ignore detailsÄAll our descriptions (of the world) are partial, filtered by:
Ø Perceptual limitsØ Cognitive limitsØ Personal values and experience
!Complementarity:ÄTwo observers’ descriptions of system may be:
Ø Redundant - if one observer’s description can be reduced to the otherØ Equivalent - if redundant both waysØ Independent - if there is no overlap at all in their descriptionsØ Complementary - if none of the above hold
ÄAny two partial descriptions (of the same system) likely to be complementaryÄComplementarity should disappear if we can remove the partiality
Ø E.g. ask the observers for increasingly detailed observations
ÄBut this is not always possible/feasible
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 25
ProblemSituation
All interventions change the system
abstractmodel of world
implementationstatement
problemstatement
change
System
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 26
Subject system
Information system
uses
builds
maintains information about
needs information about
buys services from
Usage System
Development System
Information Systems
develops theories about
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 27
Subject system
Computational System
uses results from
builds
simulatesneeds to understand
(and protect)
funds
Socio-Political System
Computational Simulations
Climate Research System
develops theories about
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 28
Subject system
Control system
uses
builds
tracks and controlsthe state of
needs to ensure safe control of
contracts
Usage System
Development System
Control Systems
affectsbehaviour
affects perceptions
affectsexpectations
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 29
Soft Systems Methodology (SSM)
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 30
Soft Systems Methodology
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 31
SSM Principles
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 32
Rich Pictures
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http://www.slideshare.net/BSBEtalk/rich-pictures-40784261
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 33
Rich Pictures…
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 34
Rich Pictures
!Don’t structure your rich picture in any way.ÄNot a timeline, storyboard, comic strip, or mindmap!
!Don’t use too many words. ÄLabels, exclamations, brief speech bubbles are okayÄSentences & paragraphs are not
!Include your personal viewsÄE.g. observations about culture, emotions, valuesÄE.g. values, beliefs, norms, social roles, etc.
!Include other points of view
Source: http://www.triarchypress.net/growing-wings---rich-pictures.html
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 35
The real value is the discussions…
Photo source: https://philipwallis.wordpress.com/2012/10/10/rich-pictures/
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 36
CATWOE
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 37
CATWOE Analysis
! Customers/Clients:Ä Who benefits/suffers from the operation of this system?
! Actors:Ä Who is responsible for implementing this system?
! Transformation:Ä What transformation does this system bring about?
!Weltanshauung:Ä What worldview justifies the existence of this system?
! Owners:Ä Who has the authority to abolish this system (or to prevent change)?
! Environment:Ä What environmental constraints impact this system?
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 38
Root Definitions
!PQR template: ÄA system to do P (what?) by means of Q (how?) in order to achieve R (why?)
!Examples:Ä“A University-owned system, operated by tenured professors, to award degrees
and diplomas to suitably qualified candidates (P), by means of assessment (in conformance to provincial standards) (Q), in order to demonstrate the capabilities of candidates to potential employers (R).
ÄC: candidate studentsÄA: tenured professorsÄT: candidate students -> degree holdersÄW: the belief that awarding degrees and diplomas is a good way to demonstrate
the quality of candidates to potential employersÄO: the University governing body (+ provincial funder)ÄE: provincial educational and assessment standards
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 39
LUMAS: Learning Systems
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University of Toronto Department of Computer Science
© 2012 Steve Easterbrook. This presentation is available free for non-commercial use with attribution under a creative commons license. 40
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