Prediction of Future Failures for Heterogeneous Reliability Field Data
This article introduces methods for constructing prediction bounds or intervals to predict the number of future failures from heterogeneous reliability field data. We focus on within-sample prediction where early data from a failure-time process is used to predict future failures from the same process. Early data from high-reliability products, however, often suffers from limited information due to small sample sizes, censoring, and truncation. We use a Bayesian hierarchical model to jointly model multiple lifetime distributions arising from different sub-populations of similar products. By borrowing information across sub-populations, our method enables stable estimation and the computation of corresponding prediction intervals, even in cases where there are few observed failures. Two applications are provided to illustrate this methodology, and a simulation study is used to validate the coverage performance of the prediction intervals.
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