Seasonal and Non-Seasonal Exponential Smoothing - Grid Search Tab

Select the Grid search tab of the Seasonal and Non-Seasonal Exponential Smoothing dialog box to access options to specify and perform a grid search of the parameter space. Strategies for identifying the optimum smoothing parameters are described in exponential smoothing.

Element Name Description
Grid search specifications Use these options to systematically evaluate the goodness of fit for sets of parameters by starting each parameter at a particular value (as specified in the Start parameter at column), and then increasing it by a small amount in consecutive steps (as specified in the Increment by column), all the way up the value specified in the Stop at column. You can view the results either for all steps (i.e., for all combinations of parameter values), or only the 10 combinations of parameter values that resulted in the smallest mean squared error for the residuals (lack-of-fit indices are also described in exponential smoothing).
Display parameters for 10 smallest mean squares When the Display parameters for 10 smallest mean squares check box is selected, the Parameter Grid Search spreadsheet will only show the parameters for the 10 smallest mean squares regardless of how many parameter values were tried. Clear this check box if you wish to review the statistics for all the parameter values.
Perform grid search Click the Perform grid search button to perform the grid search for parameters and to display the Parameter Gird Search spreadsheet. This spreadsheet reports the parameter value for each step as well as the mean error, the mean absolute error, the sums of squares, mean squares, mean percent error, and the mean absolute percent error. If the Display parameters for 10 smallest mean squares box is selected (see above), only the parameters for the 10 smallest mean squares are displayed. The smallest absolute errors is highlighted.