The modified exponentially weighted moving-average (modified EWMA) control chart is an improvement on the traditional EWMA chart. Herein, we provide more details about using various values of additional design parameter for detecting small-to-moderate shifts in process mean autoregressive fractionally integrated (ARFI(p, d)) with exponential white noise running thereon. statistical performances...

Statistical process monitoring (SPM) literature recommends the combination of Shewhart and exponentially weighted moving average (EWMA) schemes to improve ability standalone EWMA in detecting small large shifts. The resulting scheme is named combined (or composite) Shewhart-EWMA (CSEWMA) scheme. In this paper, a new single composite (denoted as SCSEWMA) for mean when parameters are known or unk...

Diagnostic laboratories are increasingly required to meet stringent quality standards, and validated assays are needed to achieve formal accreditation. Validation of test methods is often considered to be finalised when the assay parameters and characteristics have been established. However, like any process, diagnostic assays are subject to random variation resulting in shifts in the mean test...

A control chart based on the likelihood ratio is proposed for monitoring the linear profiles. The new chart which integrates the EWMA procedure can detect shifts in either the intercept or the slope or the standard deviation, or shifts simultaneously by a single chart, which is different from other control charts in literature for linear profiles. The results by Monte Carlo simulation show that...

Industrial production requires multivariate control charts to enable monitoring of several components. Recently there has been an increased interest also in other areas such as detection of bioterrorism, spatial surveillance and transaction strategies in finance. In the literature, several types of multivariate counterparts to the univariate Shewhart, EWMA and CUSUM methods have been proposed. ...

The control chart is an important statistical technique that is used to monitor the quality of a process. Shewhart control charts are used to detect larger disturbances in the process parameters, whereas CUSUM and EWMA charts are meant for smaller and moderate changes. Runs rules schemes are generally used to enhance the performance of Shewhart control charts. In this study, we propose two runs...