Template:Confidence Bounds Example

Confidence Bounds Example

In the previous example, it was found that the 10,000 landings life criterion for a 90% reliability was met. However, the estimate of 11,669.1 cycles (or landings) is very close to the requirement. Additionally, this estimate was obtained at the 50% confidence level. In other words, 50% of the time life will be greater than 11,669.1 landings, and 50% of the time life will be less. A lower confidence level is thus crucial before any decisions are made. Repeat the calculation of the previous example, and this time include a 90% lower 1-sided confidence bound on the estimation.

Solution

Using ALTA's QCP, the 90% lower 1-sided confidence bound on the 11,669.1 cycles-to-failure can be obtained.

The 90% lower 1-sided confidence bound is estimated to be 9,680.84 landings. Thus the 10,000 landings criterion is not quite met.