Balancing Loop with Stock & Flow Diagram.

The interaction of a population of Moose and Wolves.

While these pictures represent very different things there is a common essence.

Yesterday's actions are responsible for the world we experience today. And today's actions are responsible for the world that we will experience tomorrow. The "Creating the Future" model is intended to provide a better sense of the common process associated with the unexpected unfolding of the future..

This Romeo and Juliet Model was adapted by Geoff McDonnell from Michael J Radzicki (1993) Dyadic processes, tempestuous relationships, and system dynamics, System Dynamic Rev. 9 (1) :79-94

Simplest Innovation diffusion model from Sterman's Business Dynamics Ch 9

While these pictures represent very different things there is a common essence.

There's actually more to filling a swimming pool with water than you might realize.

The interaction of a population of Moose and Wolves.

This is a model depicting the interactions of the Aesop's Fable "The Boy Who Cried Wolf."

Balancing Loop with Stock & Flow Diagram.

While these pictures represent very different things there is a common essence.

While these pictures represent very different things there is a common essence.

This common archetype of systems that include relapse or recidivism allows exploration of the unintended effects of increasing upstream capacity and swamping downstream capacity. The increase in the relapse rate eventually returns to swamp upstream capacity as well. A social welfare example, based on a TANF case study, from How Small System Dynamics Models Can Help the Policy Process. N. Ghaffarzadegan, J. Lyneis, GP Richardson. System Dynamics Review 27,1 (2011) 22-44 Conference version at http://bit.ly/HlxtZj

This model is derived from the paper "Nobody Ever Gets Credit for Fixing Problems that Never Happened: Creating and Sustaining Process Improvement" by Nelson P. Repenning and John D Sterman. See Insight 752 for a causal loop version of this model.

The structure responsible for rabbit population growth.

Introduce the concept of modeling and simulation.

The Home Heating System can be used to demonstrate how we get caught in dilemmas and become victims of ourselves.

While these pictures represent very different things there is a common essence.

If we pay close attention to our actions and the typical outcomes of those actions it would be evident that there are frequently occurring patterns that develop. And there is a relation between the patterns.

When one undertakes to create a model there are a number of guidelines that are considered essential for consideration if there is to be a success with the model.

What do activities of these images have in common?

There are about fifteen known archetypes with an interesting set of relationships among them.

There is a new version of this model at

Frequently Recurring Structures

Introduce the concept of modeling and simulation.