A sample of 1000 items was placed in a test configuration such that all were operating under load. The data in the attachment contains the number still running at the end of each day for 90 days.
a. Estimate the parameters of a Weibull failure time distribution.
b. Construct 90% confidence interval for those parameters.
c. Find the reliability of this item at 30 days.
We used EXCEL for Wiebull analysis following these steps:
Firstly, we created a table on which we will perform the analysis.
We followed the steps:
1.Open Excel and into cell A1, type the label: Design A Cycles. Enter the failure data for Design A into cells A2:A91. Highlight cells A1:A91 and click on the Sort Ascending button to order the failure cycles from lowest to highest.
2.In cell B1, type the label: Rank. In cells B2:B91, type the integers 1-91
3.In Column C, put an estimate of the proportion of the population that will fail by the number of cycles ...
Estimating the parameters of a model using Weibull distribution. Constructing the 90% Confidence Interval for those parameters.