Parametric methods provide more precise results and estimate more types of functions.
When your product fails in different ways, use a failure mode analysis to evaluate the impact of each type of failure on the overall reliability. Each failure mode is assumed to be independent. By analyzing each failure mode individually, you can more easily prioritize your improvement efforts.
A company set the warranty of its new type of mufflers at 50,000 miles. The reliability group wants to assess the reliability of the new type of mufflers and to estimate the proportion of warranty claims they can expect. The measurement of interest is the number of miles driven on a muffler when a warranty claim is made.
The reliability group performs a nonparametric distribution analysis using both the Turnbull and actuarial methods.
The same automobile manufacturer is also working with the supplier of their water pumps to improve their overall reliability. To determine how to focus the improvement effort, engineers collect data on how and when water pumps fail.
The engineers perform a nonparametric multiple failure mode analysis using the Turnbull method.