A three stage variable parameters adaptive control chart

In recent decades, various adaptive X control charts with various variable parameters such as sampling interval, sample size, and control limits have been proposed to improve theefficiency of detecting the out-of-control conditions for small, medium, and large shifts. The variable parameters (VP) adaptive chart is one of these proposed charts that has an acceptable performance compared to other schemes specially for small shifts. In this article we proposed a modified version of VP chartwith three stage variable chart parameters and have compared it with Standard Shewhart chart to evaluate its performance todetect the out-of-control conditions for different amounts of shifts. Here we used two mostly used indicators to evaluate the performance of these charts which are Average Time to Signal (ATS) and Average Number of Observations to Signal (ANOS

Keywords:

Adaptive control charts , Average time to signal , Average number of observation to signal , Variable parameters