A power transformation for non-normal processes capability estimation

Abstract Process capability estimation depends on the underlying data distribution. If data is not normally distributed, other techniques for capability estimation should be taken into consideration. In this paper, we propose modified power transformation method for non-normal process capability estimation. Proposed method is compared to Box-Cox, Johnson and Abbasi-Niaki transformation method using simulation studies. In terms of transformed data and capability estimation, proposed transformation method showed better performance than Box-Cox and Abbasi-Niaki method.