Improved Monitoring of Multivariate Process Variability

Djauhari, Maman A.

doi:10.1080/00224065.2005.11980298

Cited by 64 publications

(49 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The results will show that, as mentioned in Introduction section, the stability (instability) of covariance structure does not necessarily ensure the stability (instability) of correlation structure. Those who are interested in a more general discussion on the material of this section are suggested to see (Djauhari 2005) [7] and (Djauhari et al, 2008) [43].…”

Section: The Stability Of Covariance Structurementioning

confidence: 99%

“…Look at Table 9 which presents the value of sample GVs. Based on the improved generalized variance (IGV) chart, proposed in our work (Djauhari 2005) [7], we have UCL = 2.42E-09 and LCL = 0. These estimated control limits and the value of sample GVs are plotted in Fig.…”

Section: Mspc Approachmentioning

confidence: 99%

“…Based on this concept, by using the approach in (Montgomery 2001 p. 532) [5] which is represented again in (Montgomery 2005 p. 511) [6] and by considering correlation matrix as the covariance matrix when all variables are standardized, monitoring the stability of correlation structure is equivalent to repeated tests of significance of the hypothesis that the process correlation matrix is equal to a particular matrix of constants. See (Wierda 1994) [2], (Sullivan et al, 1996) [3] and (Woodall et al, 1999) [4] for a general discussion and (Alt et al, 1988) [1], (Tang et al, 1996a) [39], (Tang et al, 1996b) [40], (Khoo et al, 2003) [41], (Khoo et al, 2004) [42], and (Djauhari 2005) [7] for monitoring covariance structure. This paper is organized as follows.…”

Section: Introductionmentioning

confidence: 99%

“…It then has been experiencing a remarkable development. See, for example, (Alt et al, 1988) [1], (Wierda et al, 1994) [2], (Sullivan et al, 1996) [3], (Woodall et al, 1999) [4], (Montgomery 2001) [5], (Montgomery 2005) [6], (Djauhari 2005) [7] and (Sullivan et al, 2007) [8], and the references there in, for historical background and its development. For an early development of the method for testing the stability of covariance structure one can consult the classical literature such as (Anderson 1958) [9].…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Monitoring the Stability of Correlation Structure in Drive Rib Production Process: An MSPC Approach

Djauhari¹,

Herdiani²

2008

TOIMEJ

View full text Add to dashboard Cite

Abstract:The stability (or instability) of covariance structure does not ensure the stability (or instability) of correlation structure. However, these stability problems are usually tested using the same approach. The most common and widely used approach is based on likelihood ratio criterion. Unfortunately, its sensitivity is not without limitation, its computational efficiency is low and it is quite cumbersome when the number of variables is large. To overcome these obstacles in monitoring the stability of correlation structure, in this paper we propose a multivariate statistical process control approach by using vector variance as multivariate dispersion measure. First, we investigate the sampling distribution of vector variance of standardized variables and then we construct a control chart. Its sensitivity is very promising, its computational efficiency is high and it is practical even when the number of variables is large. The applicability of the proposed method in monitoring the stability of correlation structure in drive rib production process at Indonesian Aerospace Ltd. will be presented.

show abstract

Section: The Stability Of Covariance Structurementioning

confidence: 99%

Section: Mspc Approachmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Monitoring the Stability of Correlation Structure in Drive Rib Production Process: An MSPC Approach

Djauhari¹,

Herdiani²

2008

TOIMEJ

View full text Add to dashboard Cite

show abstract

“…In general, they studied industrial and commercial applications, however, the statistical properties of the data utilized in the studies are similar to those in health applications. A listing of the studies is given in a large number of papers in the quality monitoring literature [10][11][12][13][14][15][16][17][18][19][20], and finally Jarrett and Pan [21,22]. These monitoring methods employ the Hotelling T2 statistic for a current sample.…”

Section: Under Mewma Modeling and Quality Controlmentioning

confidence: 99%

The Multivariate EWMA Model and Health Care Monitoring

Pan¹

2014

Int J Econ & Manag Sci

View full text Add to dashboard Cite

We introduce the construction of MEWMA (Multivariate exponentially weighted moving average) process control in the field of bio surveillance. Such introduction will both improve the reliability of data collected in bio surveillance, better interpretation of the results, improvement in the quality of results and standardization of results when more than two variables are involved. We propose sensitivity ratios as a measure of the effects of the mean shift and dispersion shift in processes under study. Using these sensitivity measures, we designed the optimal exponential weighting factor, which is consistent to results reported in control chart applications. Although ARL (average run length) is the usual measure for control chart performance in multivariate process control, it is by no means the only criterion, however, at the moment it is most widely used criterion for decision making. We suggest addition study of other criteria. For example Medial Run Length, Days to Completion, Direction of Eorrors and others.

show abstract

Multivariate Control Charts for Measurement and Attribute Data

Ryan

2011

Statistical Methods for Quality Improvement

View full text Add to dashboard Cite

Improved Monitoring of Multivariate Process Variability

Cited by 64 publications

References 13 publications

Monitoring the Stability of Correlation Structure in Drive Rib Production Process: An MSPC Approach

Monitoring the Stability of Correlation Structure in Drive Rib Production Process: An MSPC Approach

The Multivariate EWMA Model and Health Care Monitoring

Multivariate Control Charts for Measurement and Attribute Data

Contact Info

Product

Resources

About