Buehler confidence bounds for a reliability-maintainability measure

This article presents an upper confidence bound for a measure of reliability/maintainability of a series system in which component repair is assumed to restore the system to its original status. Under exponentiality of component-repair time and survival time distributions, the measure M is the ratio of expected system-repair time to expected system-survival time. Moreover, under this exponentiality assumption, the bound is uniformly minimum among all bounds of specified level that are nondecreasing functions of the maximum likelihood estimator of M. As a matter of practical interest, the measure M has been incorporated into Military Standard MIL-STD-470B and is an official statistic of the Air Force Reliability Maintainability Information System.