Accuracy Summary

If you choose a solution method with extrapolation, RunGTAP displays an accuracy summary showing how many variables are accurate in the levels to 1, 2, 3, 4, 5, or 6 figures. A modified Chernoff statistic displays overall accuracy. Accuracy of the updated data is summarised in the same way.

GEMPACK estimates a rather conservative lower bound on accuracy. In most cases results will be considerably more accurate than is indicated by the summary.

There is one summary for accuracy of variables, another for accuracy of data on file.

If you used automatic accuracy to break your simulation into several sub-intervals there will be an accuracy summary for each subinterval. Use the combobox to display which you want to see. The combo box also indicates which is the least accurate sub-interval. With GEMPACK 8 or later there is also an overall summary for variables (but not data) which allows for the accumulation of errors in all the sub-intervals.

Acccuracy is measured by an ordinal score 0...10. For each score value there is a corresponding face. Click-and-hold on the little key at the bottom of the window to see the whole range of faces.

The View menu item allows you to look again at the accuracy summary later, if it still exists (it is deleted if you change versions or load another experiment.