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Vensim Help

To start an optimization from the Simulation Control dialog click on the Optimize button.  From the Optimization wizard click on the next button.  This will allow you to change other settings associated with optimization.

Data Sources  is a list of data files to be used for data variables and calibration payoff computation.  These are required for calibration optimizations unless you have defined Data variables in the model using GET ... DATA and specified these for comparison in the payoff definition.  

Payoff Report, if checked, saves the components of the optimization criteria that have been specified to the file runname.rep.  This report includes the relative and absolute contributions to the log likelihood payoff function for each of its components.  It also generates a file called 1step.err (and 2step.err ... if the Step option has been set and Kalman Filtering is active) that gives the actual residual of model versus actual data over the course of the simulation. 1step.err can be loaded into Vensim with Dat2VDF (from the main menu Datasets>Import  Datasets>Dat2VDF ) to review these residuals. The payoff report file also includes a list of all Data, Constants and Lookups that come from outside sources along with the source file. In the case of ODBC sources the control (.vdi) file is listed.

Kalman Filtering, if checked, causes Vensim to adjust the model states during the simulation, based on the available data, using an extended nonlinear Kalman filter.  See further discussion of this below.

Step allows you to specify the number of steps ahead to report forecast errors during simulations using Kalman filtering.  This only has an impact when both Report and Filtering are on.  The files 1step.err, 2step.err and so on will be created. 2step.err, contains the results of running the model without Kalman corrections to the second available set of data points.  If this is left blank, the value 1 will be used.

Click on Finish  to begin optimization.