TY  - JOUR
T1  - Effects of Misspecification on the Economic-Statistical Design of the Coefficient of Variation Chart
AU - Chung, Yeong Wai AU - Chong, Michael Khoo Boon AU - Li, Lim Sok AU - Lin, Teoh Wei AU - Sang, Ng Peh 
JO  - Journal of Engineering and Applied Sciences
VL  - 11
IS  - 7
SP  - 1655
EP  - 1659
PY  - 2016
DA  - 2001/08/19
SN  - 1816-949x
DO  - jeasci.2016.1655.1659
UR  - https://makhillpublications.co/view-article.php?doi=jeasci.2016.1655.1659
KW  - Coefficient of variation chart
KW  -economic-statistical design
KW  -incorrect specification
KW  -increase in cost
KW  -rough approximation
AB  - The Coefficient of Variation (CV) chart monitors changes in the ratio of the standard deviation against the mean, instead of monitoring changes in the mean and/or standard deviation. The economic-statistical design of the CV chart allows practitioners to select optimal chart parameters which minimize the cost subject to constraints in the run length. However, a large number of parameters need to be estimated. This study looks at the effects when these parameters are incorrectly estimated. It was found that a minimal increase in cost is shown when the parameters are not estimated accurately, except for the incorrect specification of the shift size and the out-of-control quality cost which shows a slightly higher increase in cost. Thus, only a rough approximation is needed for most of the parameters.
ER  -