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When your failure/repair data are from more than one system, Minitab provides:

Each of these tests uses the Bartlett's modified likelihood ratio test whenever possible.

The hypotheses for these tests are:

When estimating a parametric growth curve, Minitab assumes that all systems within a single data column are from identical processes. If you reject the null hypothesis and conclude that the shapes (or scales or MTBFs) are unequal, you cannot make this assumption. In this case, you should analyze the data from different systems separately.

Note These tests are not available for interval data.