Re: When are SD models appropriate?

Joe Kilbride (
Tue, 20 Dec 94 08:52 CST

In response to my question re: "What are the criteria you use for choosing
SD models over other approaches?" Stever Robbins <> wrote:
>Having just completed MIT's course in system dynamics, my impression
>is that system dynamic models are appropriate whenever you have
>multiple feedback loops in a system, and/or long delays between cause
>and effect.

Stever has provided reasonable criteria for the use of models, i.e.,
multiple feedback loops and long delays between cause and effect.

Whether you agree with Stever's criteria or have others, my questions are:
- How specifically do you determine whether "your criteria" are
present/important in a given situation?
- What methods do you use when initially responding to client
requests that allow you to test for your criteria, whatever they
may be?
- How do you lead the client to agree with your determination
and the use of SD modeling to achieve their objectives?

My original question assumed:
1.Most of us offer more than SD models in response to client requests.
2.Clients are not initially framing their objective in SD model terms.

I'm looking for:
- criteria for the MOST APPROPRIATE USE of SD models, and
- methods for testing those criteria during request clarification.

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