Since models are often used to project (extrapolate) failure rates or MTBF's that are well beyond the range of the reliability data used to fit these models, it is very important to "test" whether the models chosen are consistent with whatever data are available.

The following describes several ways of deciding whether a model under examination is acceptable. These are:
1. Visual Tests
2. Goodness of Fit Tests
3. Likelihood Ratio Tests
4. Trend Tests

为何楼上的是英文作答