Sequential Data - Duane Example

This example appears in the Reliability growth reference.

Given the sequential success/failure data in the table below, do the following:


 * 1) Estimate the Duane parameters.
 * 2) What is the instantaneous Reliability at the end of the test?
 * 3) How many additional test runs with a one-sided 90% confidence level are required to meet an instantaneous Reliability goal of 80%?

Solution  The following figure shows the data set entered into RGA along with the estimated Duane parameters.

 The Reliability at the end of the test is equal to 78.22%. Note that this is the DRel that is shown in the control panel in the above figure.  The figure below shows the number of test runs with both one-sided confidence bounds at 90% confidence level to achieve an instantaneous Reliability of 80%. Therefore, the number of additional test runs required with a 90% confidence level is equal to $$42.2481-20=22.2481\approx 23\,\!$$ test runs.

