Annals of the Institute of Statistical Mathematics

, Volume 39, Issue 1, pp 219–225

# Bayesian analysis of hybrid life tests with exponential failure times

• Norman Draper
• Irwin Guttman
Article

## Summary

A hybrid life test procedure is discussed from the Bayesian viewpoint. A total ofn items is placed on test, failed items are either not replaced or are replaced, and the test is terminated either when a pre-chosen number,K, of items have failed, or when a pre-determined time on test has been reached. Posterior and predictive distributions are obtained under the assumption of an exponential failure distribution, and point and interval estimates are given for the mean life and the life of an untested item. The results are applied to a numerical example.

## Key words and phrases

Hybrid life test plans posterior distribution of mean life-times predictive distribution of future lifetimes single exponential distribution

## References

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Bhattacharya, S. K. (1967). Bayesian approach to life testing and reliability estimation,J. Amer. Statist. Ass.,62, 48–62.
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Epstein, B. (1954). Truncated life tests in the exponential case,Ann. Math. Statist.,25, 555–564.
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Epstein, B. (1960a). Statistical life test acceptance procedures,Technometrics,2, 435–446.
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Harter, H. L. (1978). MTBF confidence bounds based on MIL-STD-781C fixed length test results,J. Quality Technology,10, 164–169.

© The Institute of Statistical Mathematics, Tokyo 1987

## Authors and Affiliations

• Norman Draper
• 1
• 2
• Irwin Guttman
• 1
• 2