To ensure that your results are valid, consider the following guidelines when you collect data, perform the analysis, and interpret your results.
- The response should be binary
- Binary data have only two possible outcomes: the event (the item fails) or non-event (the item does not fail). If you have a continuous response that measures individual failure times, use Accelerated Life Testing.
- You must have a stress variable
- The stress variable defines the amount of stress that you put on an item during the pass/fail test. Use multiple stress values to test common stress loads. For example, to test a drill press that runs at 4 different speeds under normal-use conditions, you can include the 4 different stress levels in your test. Minitab treats the stress variable as a covariate. In addition to the stress variable, you can also enter a factor as a categorical predictor for the analysis.