Hypothesis testing for the lifetime performance index based on ranked set sampling

Abstract

Unreasonable decisions for the lifetime performance index could have serious cost for business. It is important to use an efficient sampling scheme in order to achieve better statistical inference. Ranked set sampling (RSS) is one method to potentially increase precision and reduce costs obtaining a more representative sample. In this paper, RSS and median ranked set sampling are extended for hypothesis testing of the lifetime performance index when the lifetime data have the exponential distribution with mean θ. Critical values for this test are tabulated for introduced sampling schemes and comparisons between sampling schemes are considered by obtaining the power functions. The result indicates that using RSS and median ranked set sampling increases the power of the test.

Keywords:

• ranked set sampling
• lifetime performance index
• hypothesis testing
• central limit theorem
• power function

Acknowledgments

The authors are grateful to the Associate Editor and two anonymous referees for their useful comments and suggestions on an earlier version of the manuscript, which improved the contents and presentation of the paper considerably.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by Vice President for Research and Technology of Ferdowsi University of Mashhad (FUM) [number 37447].