Template:Confidence Bounds Example: Difference between revisions
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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. | 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==== | ====Solution==== | ||
Using ALTA's QCP, the 90% lower 1-sided confidence bound on the 11,669.1 cycles-to-failure can be obtained. | Using ALTA's QCP, the 90% lower 1-sided confidence bound on the 11,669.1 cycles-to-failure can be obtained. | ||
[[Image:ipl_example2_qcp.gif | [[Image:ipl_example2_qcp.gif|center|500px|]] | ||
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. | 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. | ||
Revision as of 06:58, 9 August 2012
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.