Statistical bootstrap in the problem of availability factor estimating: example of SRs 1200 excavator reliability

Abstract

It is difficult sometimes to estimate the confidence intervals for the particular statistics, because there is no so far for some of them mathematical expression for their variance. That is true for availability factor—complex characteristic of restorable items reliability. Statistical bootstrap, as one of resampling methods, has been applied to this problem. Availability of subsystems of rotary excavator has been considered using the proposed method. The data of reliability were collected in Serbia, at open coal development. The proposed model is based on statistical bootstrap method. On the basis of proposed method, the availability factor confidence intervals and histograms for excavator subsystems were built. The availability factor of the system in a whole was also evaluated. The results, as well as comparison with existing approaches, are presented. The attempt has been made to estimate the risk factor of subsystems using the data of availability.