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I would also suggest the recent interesting paper from James Lyneis and Alexander Pugh III, presented at the ISDC97: "Automated vs. Hand Calibration of SD models". The interesting conclusions that "hand calibration" is not as an art as it may seem and that it produces results &qu...

To me this is an interesting question. Optimisation may imply automated callibration and hence, by replacing human reasoning, it may prevent an important source of learning. It may also reduce the intensity with which the modeller questions the model validity and tries alternative *structures* (I as...

You may find a discussion about the several simulation techniques (discrete & continuous, including SD) as applied to problems in OR/MS, in the following reference: Pidd, M (1993) "Computer Simulation in Management Science", John Wiley & Sons, Chicester: England. Regards, Alexandre...

I would like to add to this discussion an element of comparison between "word and arrows" influence diagrams (ID), and "level ate" diagrams (LRD): the level of formality. Although this might only reflect personal experience, it seems to me that the emergence of the ID representat...

I totally agree Jaideeps remark about the importance of both data and structural strenght of any model, and of coutse in SD modelling. As I mentioned before, if systems have theory-parameters these must be calibrated with care. The same applies for the problem of Chaos, as noted by Jaideep. I also a...

In reply to Jim Hines posting: "What is the value of "adjusting the last bits of some parameter values just to get it right! (while feeling confident in the model structure)"? If, as Alexandre says, its "wasting time" doing it by hand at this stage, its also wasting time to ...