Statistical Process Control Charts Based on the Exponentiated Janardan Distribution for Skewed Lifetime Data

Karupaiah K, Zhang L and Platonova LE

Published on: 2026-05-01

Abstract

Statistical process control techniques are widely used for monitoring process quality; however, traditional control charts are mainly based on the assumption of normality, which is often violated in practice. This study proposes a control chart based on the Exponentiated Janardan Distribution to effectively monitor skewed and non-normal lifetime data. The fundamental properties of the distribution, including the survival function, hazard function, and moments, are derived and utilized for constructing control limits. A numerical illustration is presented to demonstrate the applicability of the proposed control chart. The resulting control chart successfully detects out-of-control signals, highlighting its sensitivity to process shifts. The truncation of the lower control limit further supports its suitability for lifetime data analysis. The proposed control chart provides a flexible and robust alternative to conventional normal-based charts and is applicable in quality control, reliability engineering, and healthcare monitoring.