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.
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====Solution====
====Solution====
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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.
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[[Image:ipl_example2_qcp.gif|thumb|center|500px|]]
[[Image:ipl_example2_qcp.gif|center|500px|]]
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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.
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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.

Ipl example2 qcp.gif

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.