Multiple-steps step-stress accelerated life tests: a model and its spreadsheet analysis

We present a simple and yet powerful method for analysing data from multiple-censored, multiple-steps step-stress accelerated life tests. The method is a simplification of Tang et al. (1996) and its extension to handle interval data and other forms of censoring. To further simplify the procedure of analysing step-stress data, which has been made unduly complex in the existing literature, we implement the proposed method using spreadsheet programming on Excel. The corresponding templates for different types of data are presented along with examples taken from the literature.