The performance of an X-bar chart is usually studied under the assumption that the process standard deviation is well estimated and does not change. This is, of course, not always the case in practice and X-bar charts are not robust against errors in estimating the process standard deviation or changing standard deviation. In this paper, the use of an exponentially weighted moving average (EWMA...

Cumulative sum (CUSUM) and exponentially weighted moving average (EWMA) control charts are commonly used to detect small changes in the parameters of production processes. Recently, a new control structure was introduced, named as mixed EWMA–CUSUM control chart, which combined both charts. The current study provides a detailed comparison of these three types of control charts when the process p...

Statistical technique used to analyze quality problems and improve process performance is Process Control (SPC). In this study, multivariate control chart the of graduates Statistics Study Program, FMIPA USK, namely using Multivariate Exponentially Weighted Moving Average (MEWMA) average, Variance (MEWMV) variability, analysis Capability assess entire process. Data secondary data, GPA duration ...

In recent years, the monitoring of compositional data using control charts has been investigated in Statistical Process Control field. this study, we will design a Phase II Multivariate Exponentially Weighted Moving Average (MEWMA) chart with variable sampling intervals to monitor based on isometric log-ratio transformation. The Time Signal be computed Markov chain approach investigate performa...

Background and objectives: Risk-adjusted Bernoulli control chart is one of the main tools for monitoring multistage healthcare processes to achieve higher performance and effectiveness in healthcare settings. Using parameter estimates can lead to significantly deteriorate chart performance. However, so far, the effect of estimation error on this chart in which healthcare ...

To monitor time and magnitude, different types of control charts have been proposed in the literature. This article proposes a new maximum exponentially weighted moving average (Max-EWMA) chart by assuming Weibull distribution. The test-statistic Max-EWMA consists two EWMA statistics, where one statistic is used for monitoring magnitude while other to interval between events. performances asses...

Distribution-free or nonparametric control charts are used for monitoring the process parameters when there is a lack of knowledge about underlying distribution. In this paper, we investigate single distribution-free triple exponentially weighted moving average chart based on Lepage statistic (referred as TL chart) simultaneously shifts in unknown location and scale univariate continuous The de...