REPLY Definition of exogenous (SD6851)

[SDMAIL Douglas Franco]

Posted by  "Douglas Franco" <dfranco at cantv.net>

Sometimes, exogenous inputs determine behavior.
There has been concern about what it means an exogenous variable. A sine 
wave is presented as an evidence of the fuzziness of the concept.
Reference modes are exogenous inputs to the modeler; if you can build 
the exogenous input using stocks and flows, then it is a reference mode 
rather than an exogenous input. Stocks and Flows representation unfold 
the root causes of pathology and let the success be. Once the "exogenous 
inputs" are properly structured, the solution is often trivial, because 
the feedbacks are made explicit.

Douglas Franco
Posted by  "Douglas Franco" <dfranco at cantv.net>
posting date  Tue, 1 Apr 2008 10:02:01 -0400