The (α, β)-Precise Estimates of MTBF and MTTR: Definitions, Calculations, and Induced Effect on Machine Efficiency Evaluation

Abstract

This paper is intended to explore how many measurements of machine up- and downtimes are necessary to calculate reliable estimates of MTBF and MTTR, and what would be the resulting effect on the machine efficiency evaluation. This issue is addressed by introducing the notion of (α, β)-precise estimate, where α characterizes the accuracy of the estimate and β its likelihood (probability). Based on this notion, the smallest number of measurements, n⁎ (α, β), which leads to the desired estimate, is evaluated and utilized for investigation of the induced machine efficiency estimate.