REPLY SD Impact on National Government policies (SD6198)

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Posted by  "Erling Moxnes" <Erling.Moxnes at geog.uib.no>

A few reflections on SD growth and impact.

Starting with Jay Forrester and having 1000 society members after 50 
years, implies a growth rate of 15 percent per year. If that continues 
there will be 1 million members in another 50 years. With 50 percent 
attendance at the conferences, we will need much space for the plenary 
sessions!

Forecasts like this one, as well as the more pessimistic ones, suffer 
from a typical bias towards hard data. More important for me is the 
enthusiasm I felt when first learning SD, as well as the enthusiasm I 
see among our students and clients. In this lies a lasting potential for 
growth and impact.

A growing number of experimental studies demonstrate the complexity of 
even small dynamic models. Many "elevator speech" instructions fail to 
improve the results. Changing people's existing mental models is hard, 
particularly when one has to start from scratch every time. This is why 
I think Forrester's call for K12 education in SD is very important. Much 
work is needed to succeed; we have just started.

Since dynamics are complex, I also think we should strive for simplicity 
and clarity in models and presentations. I see more happy faces and more 
enthusiasm when teaching simple cases rather than complex ones. Most system 
dynamicists seem to underestimate the complexity of their work. Every year 
I show the new students a moderately comprehensive causal loop diagram from 
one of our conferences. I give them 2 minutes to count the feedback loops. 
The answers are approximately uniformly distributed from 1 to 6! Who ever 
gave the audience a 2 minute break to figure out the number of loops in 
their CLD? Sometimes one needs to complicate models for research purposes 
and to answer questions from clients. However, to make major points and to 
change faulty mental models do you ever need more than two or three stocks??

Whishing you all a happy and simple new year,

Erling Moxnes

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Erling Moxnes
System Dynamics Group
Dept. of Geography
University of Bergen
Posted by  "Erling Moxnes" <Erling.Moxnes at geog.uib.no>
posting date  Thu, 18 Jan 2007 14:38:11 +0100