An EWMA-type chart based on signed ranks with exact run length properties. Issue 4 (4th March 2021)

• Record Type: Journal Article
• Authors: Perdikis, T.; Psarakis, S.; Castagliola, P.; Celano, G.
• Is Part Of: Journal of statistical computation and simulation. Volume 91:Issue 4(2021)
• Page Start: 732
• Page End: 751
• Publication Date: 2021-03-04
• Subjects: Nonparametric control chart -- Wilcoxon signed rank statistic -- phase II control chart; Mathematical statistics -- Data processing -- Periodicals; Digital computer simulation -- Periodicals; 519.5028505
• DOI: 10.1080/00949655.2020.1828415
• Languages: English
• ISSNs: 0094-9655

Abstract

ABSTRACT: In this work, a new distribution-free Phase II EWMA-type chart based on the Wilcoxon signed rank statistic is introduced and its exact Run Length properties are discussed. A proper discrete Markov-chain approach is used for the determination of the Average Run Length in the in-control and out-of-control process operating conditions and its exact performance is derived without any knowledge of the distribution of sample observations. In addition, an algorithm for the determination of the chart's optimal design has been developed. Moreover, the performance of our proposed chart is compared with several existing nonparametric schemes available from the literature. Finally, two illustrative examples are provided to show the practical implementation of our proposed chart.