For a best fit (BF) or best fit recompensate (BFRE) ellipse, you can choose to remove outliers based on the distance from the best fit feature. This allows the removal of anomalies that arise in the measurement process.
PC-DMIS first fits an ellipse to the data and then determines which points are outliers based on the standard deviation multiple. It then does the following:
Recalculates the best fit ellipse with those outliers removed.
Checks for outliers again.
Recalculates the best fit ellipse.
Continues repeating this process until no more outliers exist or until PC-DMIS cannot compute the ellipse (PC-DMIS can't compute the ellipse if there are fewer than 4 data points).