The Design Space Profiler report contains a profiler graph for the expected proportion of responses that would be in-spec given the limits on the factors. For each factor, there are two solid curves that model the in-spec portion and two dashed vertical lines that represent the current operating limits. When the profiler is launched, the operating limits are set to the lower and upper factor limits. The blue curve represents the response in-spec portion as the lower operating limit is changed for the corresponding factor. The red curve represents the response in-spec portion as the upper operating limit is changed for the corresponding factor.
Note: The Design Space Profiler respects locked factors if the factor is locked in the Prediction Profiler before the Design Space Profiler is launched for the first time. If a factor is locked, the profiler for that factor contains only a solid vertical line at the locked value. See “Set or Lock Factor Values”.
The Design Space Profiler report also contains several tables. The first table contains the InSpec Portion and Volume Portion for the current limits. The InSpec Portion represents the proportion of simulated responses that are in-spec at the current factor limits. The Volume Portion represents the proportion of the total data that is within the current factor limits. If there is more than one response, this value is the combined in-spec portion for all of the responses. There is a factor table that shows the current lower and upper operating limits for each of the factors. These limits can be edited, but are automatically updated if the limits are changed on the graph or by using the Move Inward or Move Outward buttons. There is a response table that shows the current lower and upper specification limits for the responses, as well as the error standard deviation. If the prediction formula contains a column property that specifies sigma, the response table error standard deviation field is automatically populated with that value. You can edit the fields in the response table if desired and the Design Space Profiler report is updated automatically.
You can change the factor operating limits in a number of ways.
• In the profilers, you can drag the vertical lines to change the operating limits.
• You can manually update the operating limits by entering new values in the factor table.
• Use the Move Inward and Move Outward buttons for optimal limit adjustment. When you use the Move Inward button, the in-spec portions for a change of an increment of 1/20th of the factor range in each operating limit for each factor are compared across all limits. The factor operating limit adjustment that maximizes the improvement of the in-spec portion is implemented. The goal is to narrow the ranges of the operating limits enough to achieve an acceptable in-spec portion while maintaining a wide enough range that allows for expected variation in the factors.
The Design Space Profiler also supports categorical factors. Instead of setting operating limits, you can restrict the levels of the categorical factors to explore how the in-spec portion is affected.