Synopsis of “Towards a Core Set of Archetypal Structures in System Dynamics”E.F.Wolstenholme and D.A.Corben

Synopsis byLaura ShireySDOE 683March 2009

Additional Reading

“Towards the definition and use of a core set of archetypal structures in system dynamics” http://www.symmetricsd.co.uk/files/Towards_definition_of_a_core_set_of_archetypal_structures.pdf

E. F. Wolstenholme

Purpose

Condense the infrastructure and activity archetypes (Richmond 1988) and 8 relevant generic structures (Senge 1990) into a minimum set.

Classify generic archetypes as problem and solution

DefinitionsSystem Archetypes represent an attempt to classify

system structures and behaviors and, in particular, counter intuitive behaviors.

-E.F.Wolstenholme and D.A.Corben

System DynamicsA method for understanding the dynamic behavior of complex systems. The basis of the method is the recognition that the structure of any system — the many circular, interlocking, sometimes time-delayed relationships among its components — is often just as important in determining its behavior as the individual components themselves.

- Wikipedia.org

Archetypes in System Dynamics

“System Dynamics in general, and archetypes in particular, describe systems in terms of feedback loops arising from a combination of actions (rates of change) and outcomes (levels).”

-E.F.Wolstenholme and D.A.Corben

Feedback Loops

Actions to attempt control, using balancing (negative) feedback effects

Actions which attempt to initiate growth, using reinforcing (positive) feedback effects

Examine responses to actions to understanding behavioral insights and in turn systems thinking and system dynamics

Four possible two-loop archetypes represent the action-outcome-responses.

Generic Two Loop System Archetype

The characteristics of the archetype First, it is composed of an intended consequence

feedback loop which results from an action initiated in one sector of an organization with an intended consequence over time in mind.

Second, it contains an unintended consequence feedback loop, which results from a reaction within another sector of the organization or outside.

Third, there is a delay before the unintended consequence manifests itself.

Fourth, there is an organizational boundary that ‘‘hides’’ the unintended consequence from the ‘‘view’’ of those instigating the intended consequences.

Fifth, that for every ‘‘problem’’ archetype, there is a ‘‘solution’’ archetype.

Four Generic Problem Archetypes Growth intended- stagnation/decline achieved

Underachievement, where intended achievement fails to be realized

Control intended- unwanted growth achieved Out of control, where intended control fails to be

realized Control intended- compromise achieved

Relative achievement, where achievement is only gained at the expense of another

Growth intended- at expense of others Relative control, where control is only gained at the

expense of others

The reduced set of four generic archetypesR = reinforcing feedback loop; B = balancing feedback loop; o = opposing action

Mapping the Semi-Generic Problem Archetypes

Growth Intended – Stagnation Achieved Limits to Growth/Success Tragedy of the Commons

Control Intended- Unwanted Growth Achieved Fixes that Fail Shifting the Burden

Control Intended – Compromise Achieved Escalation Drifting Goals

Growth Intended – At the Expense of Others Success to be Successful

Underachievement Archetype

Out of Control Archetype

Relative control archetype

Relative achievement archetype

Questions

1. How can understanding these archetypes assist decision makers in having foresight/forecasting?

2. Does understanding these archetypes assist communication across boundaries?

3. How does this apply to chaos?