Why predicting outliers in software is a good thing to do!

A software reliability model is used to predict outliers, that is, values that significantly depart from the expected or mean values. In contrast with most projects that cleanse outliers from their databases because their presence distorts results, we tend to like outliers because by predicting them, we can help ensure safety in critical systems. We use the Space Shuttle failure data to make predictions of whether reliability goals are met if outliers should occur during test or the operational mission. In addition, prospective Shuttle software releases are analyzed to detect possible anomalous behavior that would call for re-inspection of the software to bring it into conformance with reliability specifications.