g. p. richardson system dynamics conference, seoul, korea, july 2010 1 rockefeller college of public...
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G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
On the Foundations of System Dynamics
George P. RichardsonRockefeller College of Public Affairs and Policy
University at Albany
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Motivation
• Feedback loops• Stocks and flows• Behavior-over-time graphs• System archetypes• Computer simulation• STELLA, Vensim, PowerSim• Nonlinearity, loop dominance• Compensating feedback• Policy resistance• Dynamic complexity
• What is really deeply important about systems thinking and system dynamics?
• …in education?
• …in corporate decision making and policy design?
• …in public policy and governance?
• …in theory building?
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
The Claim:
The deep foundation is the Endogenous Point of View
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Forrester’s Stated Foundations: The four threads (1958)
• Advances in computing technology• Growing experience with computer simulation• Improved understanding of strategic decision making• Developments in the understanding of the role of
feedback in complex systems• But it took ten more years before Forrester published the
deep foundation of the system dynamics approach
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Forrester’s Four-Tiered HierarchyUrban Dynamics, Market Growth as Influenced by Capital Investment
• Closed boundary around the system• Feedback loops as the basic structural elements within
the boundary• Level (stock) variables representing accumulations
within the feedback loops• Rate (flow) variables representing activity within the
feedback loops
• Goal, Observed condition, Detection of discrepancy, Action based on discrepancy
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Forrester’s Four-Tiered HierarchyUrban Dynamics, Market Growth as Influenced by Capital Investment
• “Closed boundary around the system”!
• The “Closed boundary” signifies Forrester’s Endogenous Point of View.• It comes before feedback loops, stocks and flows,
graphs over time, and all the rest of what we do.
• It has top billing.
• It is the deep foundation of systems thinking.
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
An Example
• Exogenous point of view• Sam is always mean to Pam.
• It’s all his fault.
• If he would be nicer, Pam’s life would be better.
• Endogenous point of view• Maybe there is something
Pam is doing …
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Exogenous and Endogenous Points of View
• “The fault, dear Brutus, is not in our stars, but in ourselves …”
• Cassius, in Shakespeare’s Julius Caesar (1599)
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Exogenous and Endogenous Points of View
• “We have met the enemy and He is Us.”
• Walt Kelly’s Pogo, originally on an Earth Day poster, 1970.
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Exogenous and Endogenous Points of View
• Man is not the creature of circumstances. Circumstances are the creatures of men.
• Benjamin Disraeli, Vivian Grey, 1827
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Feedback Loops are a Consequence of the Endogenous Point of View
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Expanding the Boundary to Enable an Endogenous Point of View
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Endogeneity and Feedback
Feedback loops enable the endogenous point of view and give it structure.
[Richardson 1991]
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Examples
• Global Warming• Flood Damage• Terrorism
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
The Global Warming Discussion
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
400,000 Years of Temperature Data
http://www.landcareresearch.co.nz/research/globalchange/climate_change.asp
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
100 Years of Temperature Data
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
CO2 Concentration
http://www.landcareresearch.co.nz/research/globalchange/climate_change.asp
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Methane
http://www.landcareresearch.co.nz/research/globalchange/climate_change.asp
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Yes, the peaks line up.
But if it’s been going on for 400,000 years, why do we now think humans are to blame?
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Milankovitch Cycles (1,000,000 yrs)There are strong exogenous, structural effects on climate change.
[Source: http://en.wikipedia.org/wiki/Malankovitch_cycles]
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Both perspectives involve stock-and-flow / feedback dynamics
The water cycleThe carbon cycleHeat trapping- Water vapor- Atmospheric CO2- Other GH gases- Cloud cover
Heat reflecting- Ice albedo- Cloud albedo- Aerosols
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Both may even acknowledge reinforcing feedback loops
Water vaporCloud coverIce albedo
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
The Global Warming Debate
• Exogenous view: We are in the warm phase of a 100,000 year cycle caused by exogenous, structural characteristics• Policy implication: Adapt to the inevitable
• Endogenous view: Human activity is exacerbating the natural cycle• Policy implication: Alter human habits to minimize the
coming tragedies
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Largely Exogenous Views of Terrorism (various internet sources; see paper)
• Ethnicity, nationalism/separatism, poverty and economic disadvantage, globalization, (non)democracy, Western society, disaffected intelligentsia, dehumanization, and religion
• Marginalization, ethnicity and nationalism, religion, cultism, free flow of weapons, training of non-military personnel, no pure democracy present
• Belief causes terrorism.
• Foreign domination and control of Muslim resources, the hatred of the Western way of life. alienation. poverty and illiteracy. moral decadence of the West. the West's support for Israel.
• Economic deprivations, political injustices, foreign occupation and denial of fundamental rights including the right to self-determination
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Terrorist Incidents Over Time(Source: http://www.start.umd.edu/gtd/features/GTD-Data-Rivers.aspx)
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Endogenous View of Structure and Dynamics of Terrorist Cells
New recruits
Terrorist group Losses
Terrorist actions
Suppression activities
Zeal
Peripheral support
Funding
Martyrs to the cause
(R)
(R)
(B)
(R)
(R)
(R) (B)
(R)
(R)
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Terrorism
• Exogenous view: Violent forces exist that threaten others, and they are growing.• Policy implication: Defend to prevent harm; attack to weaken
or eliminate the violent forces.
• Endogenous view: Violent forces interact with defenses and attacks to create the rising tensions we observe.• Policy implication: Defend to prevent harm; minimize
behaviors that create nasty reinforcing loops; maximize creation of beneficial reinforcing loops; work toward cross-cultural understandings.
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
An Exogenous View of Flood Damage
Flood severity
Flood frequency
Structural mitigation policies
Flood damage
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Flood Damages (Deegan 2007, NOAA)
• Increasing coastal populations?Increasing coastal populations?• Increasing severity of floods (global warming)?Increasing severity of floods (global warming)?• 1968 National Flood Insurance legislation?1968 National Flood Insurance legislation?
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
A Model of Floods in whichIdentical Floods Do Not Cause Identical Damage
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Underlying Causes of Damage:Evolution of Land Use and Natural Barriers
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
An Endogenous View of Flood Damage
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Flood Damage
• Exogenous view: Floods happen sometimes; the greater the flood, the worse the damage.• Policy implication: When floods happen to occur, recover and
rebuild.
• Endogenous view: Damage occurs when hazard meets vulnerability; vulnerability is a result of people policies• Policy implication: Recognize human role in damage. Work
with stakeholders to minimize vulnerabilities.
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Governing
• The great insight of servomechanisms engineering: • The act of trying to govern / manage / control
generates system dynamics of its own.
• “A closed-loop control system is thus an error-sensitive system and, being such, it acquires certain peculiarities and idiosyncrasies which, in large measure, are the reasons for this book” (Gordon Brown, 1948).
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
A Forrester Story Vividly IllustratingControl Generating Dynamics of its Own
One time we were making feedback control systems with some high-powered applications – I think it was a 10-horsepower motor with a hydraulic control system to drive probably some kind of military gun mount. I remember one night I was working with it, and something went wrong.
It had become unstable, and it began to go back and forth at the maximum speed that the 10-horsepower motor would drive it. Some of the hydraulic lines had broken, and it was spraying oil into the air, and I was trying to get it stopped.
As I rushed over to try to turn it off, I slipped in the oil on the floor. What I remember is seeing the rainbows in the oil spray up against the lights… which is a lesson on oscillatory behavior.
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
The “X/N” Matrix
Striving for understanding and
leverage, but failing
Achieving understanding and
leverage
Accepting fate, Predicting, Preparing
Confused, Misguided, Misguiding
Exogenous Endogenous
True (Predominant) State of Affairs
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Pre
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Ana
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G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
Is Endogeneity the Foundation ofAll Systems Approaches?
• Suggested characterization: “Systems thinking is the mental effort to uncover endogenous sources of system behavior.”
• Maybe.
• But certainly, the Endogenous Point of View is fundamental to systems thinking in the system dynamics tradition.
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
The Foundation of System Dynamics
• Suggested definition:
“System dynamics is the use of informal maps and formal models with computer simulation to uncover and understand endogenous sources of system behavior.”
G. P. RichardsonSystem Dynamics Conference, Seoul, Korea, July 2010
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Rockefeller College of Public Affairs and PolicyRockefeller College of Public Affairs and PolicyUniversity at AlbanyUniversity at Albany
The Foundation of System Dynamics
• What do systems thinkers and system dynamicists do?
• We use systems thinking, management insights and computer simulation to
• hypothesize, test, and refine endogenous explanations of system change, and• to use those explanations to guide policy and decision making.