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Related papers: Stein EWMA Control Charts for Count Processes

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We study optimal design of the Exponentially Weighted Moving Average (EWMA) chart by a proper choice of the smoothing factor and the initial value (headstart) of the decision statistic. The particular problem addressed is that of quickest…

Applications · Statistics 2014-11-07 Aleksey S. Polunchenko , Grigory Sokolov , Alexander G. Tartakovsky

Over the years, the most popularly used control chart for statistical process control has been Shewhart's $\bar{X}-S$ or $\bar{X}-R$ chart along with its multivariate generalizations. But, such control charts suffer from the lack of…

Computation · Statistics 2012-11-20 Kushal Kr. Dey , Kumaresh Dhara , Bikram Karmakar , Sukalyan Sengupta

A multivariate control chart is designed to monitor process parameters of multiple correlated quality characteristics. Often data on multivariate processes are collected as individual observations, i.e. as vectors one at the time. Various…

Methodology · Statistics 2019-12-23 Jimoh Olawale Ajadi , Zezhong Wang , Inez Maria Zwetsloot

Monitoring of project performance is a crucial task of project managers that significantly affect the project success or failure. Earned Value Management (EVM) is a well-known tool to evaluate project performance and effective technique for…

Applications · Statistics 2019-12-20 Nooshin Yousefi , Ahmad Sobhani , Leila Moslemi Naeni , Kenneth R. Currie

This note introduces a new Bayesian control chart to compare two processes by monitoring the ratio of their percentiles under Weibull assumption. Both in-control and out-of-control parameters are supposed unknown. The chart analyses the…

Applications · Statistics 2015-07-01 Pasquale Erto

In preliminary analysis of control charts, one may encounter multiple shifts and/or outliers especially with a large number of observations. The following paper addresses this problem. A statistical model for detecting and estimating…

Applications · Statistics 2014-03-05 Issac Shams , Saeede Ajorlou , Kai Yang

Panel count data describes aggregated counts of recurrent events observed at discrete time points. To understand dynamics of health behaviors, the field of quantitative behavioral research has evolved to increasingly rely upon panel count…

This article aims to consider a new univariate nonparametric cumulative sum (CUSUM) control chart for small shift of location based on both change-point model and Mann-Whitney statistic. Some comparisons on the performances of the proposed…

Methodology · Statistics 2013-05-21 Dabuxilatu Wang , Qiang Xiong

This paper deals with phase II, univariate, statistical process control when a set of in-control data is available, and when both the in-control and out-of-control distributions of the process are unknown. Existing process control…

Applications · Statistics 2009-06-09 Snigdhansu Chatterjee , Peihua Qiu

Control charts for process monitoring are widely used in practice. Most control charts require the monitored (residuals) process to be serially independent (and to satisfy specified distributional assumptions), whereas undetected dependence…

Methodology · Statistics 2026-05-27 Christian H. Weiß , José M. Amigó

During the recent years there was an increased interest in studying the performance of different types of control charts, under various distributional models for continuous proportions, such as percentages and rates. In this work we…

Methodology · Statistics 2025-02-05 Athanasios C. Rakitzis

In this note, we revisit the $g$ and $h$ control charts that are commonly used for monitoring the number of conforming cases between the two consecutive appearances of nonconformities. It is known that the process parameter of these charts…

Applications · Statistics 2021-01-25 Chanseok Park , Min Wang

Stein's method is applied to obtain a general Cramer-type moderate deviation result for dependent random variables whose dependence is defined in terms of a Stein identity. A corollary for zero-bias coupling is deduced. The result is also…

Probability · Mathematics 2013-02-06 Louis H. Y. Chen , Xiao Fang , Qi-Man Shao

The traditional variable control charts, such as the X-bar chart, are widely used to monitor variation in a process. They have been shown to perform well for monitoring processes under the general assumptions that the observations are…

Methodology · Statistics 2022-12-22 Chanseok Park , Linhan Ouyang , Min Wang

Phase I distribution-free runs- and patterns-type control charts are proposed for monitoring the unknown target value (or location parameter) for both continuous and discrete individual observations. Our approach maintains the nominal…

Applications · Statistics 2025-11-18 Tung-Lung Wu

To use control charts in practice, the in-control state usually has to be estimated. This estimation has a detrimental effect on the performance of control charts, which is often measured for example by the false alarm probability or the…

Methodology · Statistics 2013-07-30 Axel Gandy , Jan Terje Kvaløy

There is a considerable amount of ongoing research on the use of Bayesian control charts for detecting a shift from a good quality distribution to a bad quality distribution in univariate and multivariate processes. It is widely claimed…

Applications · Statistics 2017-12-19 Amir Ahmadi-Javid , Mohsen Ebadi

Zero inflation is a common nuisance while monitoring disease progression over time. This article proposes a new observation driven model for zero inflated and over-dispersed count time series. The counts given the past history of the…

Statistics Theory · Mathematics 2021-05-14 Vurukonda Sathish , Siuli Mukhopadhyay , Rashmi Tiwari

Nonparametric control charts that can detect arbitrary distributional changes are highly desirable due to their flexibility to adapt to different distributional assumptions and distributional changes. However, most of such control charts in…

Methodology · Statistics 2017-12-15 Jun Li

The memory-type control charts, such as EWMA and CUSUM, are powerful tools for detecting small quality changes in univariate and multivariate processes. Many papers on economic design of these control charts use the formula proposed by…

Applications · Statistics 2020-09-22 Amir Ahmadi-Javid , Mohsen Ebadi