A Class of Tests for Testing Better Failure Rate at Specific Age Distribution With Randomly Right Censored Data

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Gamal R. Elkahlout


A device has a better failure rate at specific age t0 property, denoted by BFR-t0 if its failure rate r(t) increases for t≤t0 and for t>t0, r(t) is not less than its value at t0. A test statistic is proposed to test exponentiality versus BFR-t0 based on a randomly right censored sample of size n. Kaplan-Meier estimator is used to estimate the empirical life distribution. Properties of the test are measured by power estimates, estimated risks, and test of normality. The efficiency loss due to censoring is investigated by using tests for censored sample data.

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