Detecting Outliers in Gamma Distribution

Abstract

Abstract Zerbet and Nikulin presented the new statistic Z k for detecting outliers in exponential distribution. They also compared this statistic with Dixon's statistic D k . In this article, we extend this approach to gamma distribution and compare the result with Dixon's statistic. The results show that the test based on statistic Z k is more powerful than the test based on the Dixon's statistic. Keywords: Dixon's statisticGamma sampleOutlierPower of the testSlippage hypothesisTest of ChauvenetUpper outlier Z statisticMathematics Subject Classification: 62xx62Fxx62F03 Acknowledgments The authors are thankful to the referees for their valuable comments. We are also wish to acknowledge partial support from Ordered and Spatial Data Center of Excellence of Ferdowsi University of Mashhad. This research was supported by a grant from Ferdowsi University of Mashhad (No. MS87031JAB). Notes Upper value in each cell refers to α = 0.05 and lower value to α = 0.1. Upper value in each cell refers to α = 0.05 and lower value to α = 0.1.