To create a test plan, you need information about the data you expect to collect. You can obtain planning information from:
- Design specifications
- Expert opinions
- Previous studies or small pilot studies
For an estimation test plan, you must do one of the following:
- Provide planning values for both unknown parameters (scale and shape or location and scale). Alternatively, you can provide planning values for one or two of the percentiles and Minitab will calculate the value of the unknown parameters.
- Provide a planning value for the unknown scale (Weibull or exponential distribution ) or location (other distributions) parameter when the shape (Weibull distribution) or scale (other distributions) is known.
For an accelerated life test plan, you must provide the shape (Weibull distribution) or scale, and planning values for one of the following:
- Percentiles at two different stress levels
- One percentile and the intercept
- One percentile and the slope
- The intercept and the slope
The slope represents the activation energy when the Arrhenius relationship is chosen and the assumed distribution is Weibull, exponential, lognormal, or loglogistic.