Estimation of time-to-failure distribution derived from a degradation model using fuzzy clustering

Some life tests are terminated with few or no failures. In such cases, a re cent approach is to obtain degradation measurements of product performance that may contain some useful information about product reliability. General ly degradation paths of products are modeled by a nonlinear regression mode l with random coefficients. If we can obtain the estimates of parameters un der the model, then the time-to-failure distribution can be estimated. In s ome cases, the patterns of a few degradation paths are different from those of most degradation paths in a test. Therefore, this study develops a weig hted method based on fuzzy clustering procedure to robust estimation of the underlying parameters and time-to-failure distribution. The method will be studied on a real data set. Copyright (C) 2000 John Wiley & Sons, Ltd.