QUERY Rate Equations

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""michi b""
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QUERY Rate Equations

Post by ""michi b"" »

Posted by ""michi b"" <michi9999@gmail.com> Dear SD colleagues,

I have a question concerning the technical side of SD modelling.

If we have a system composed of 2 stocks. One stock S2 is changing very slowly so that we can regard it as a constant. The second stock S1 has an inflow and an outflow. Both flows are determined by S2. Can there be a situation in which we get a net-flow equation of S1 like

dS1 = a * S2 * S2 ?

Or put differently, can there be a situation in which the information about the level of S2 is used multiple times in the flow equation? In my view this would mean, that the informaion that determines the flow equation does not come from within the model but is somehow preprocessed outside the model. I would say that there should be 2 stocks S2 and S3 with the same level in order to model such a situation.

Can you imagine an example that would lead to an equation described above?

Thank you very much!

kind regards

Michael
Posted by ""michi b"" <michi9999@gmail.com> posting date Sat, 30 Dec 2006 00:30:15 +0100 _______________________________________________
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