Title :
Statistical Process Control for Small Shifts Based on Skewed Distribution
Author :
Hai-yu, WANG ; Ji-chao, XU
Author_Institution :
Zhongyuan Univ. of Technol., Zhongyuan
Abstract :
EWMA control chart can be designed to quickly detect small shifts in the mean of a sequence of independent normal observations. But this chart cannot perform well for skewed distribution. The main goal of this article is to suggest a EWMA control chart method using to monitoring small shifts in a skewed distribution. Weighted Variance method is introduced to construct a kind of EWMA chart for skewed distribution and the optimization design of this chart is given by using Average Run Length as a performance assessment criteria. Pair of asymmetry control limits could be evaluated by sample dates in skewed distribution. The advantage of this method in detecting little drift for skewed distribution was illustrated by comparing with others control charts.
Keywords :
control charts; statistical process control; average run length; exponentially weighted moving average control chart; performance assessment; skewed distribution; statistical process control; weighted variance method; Conference management; Control charts; Design engineering; Design optimization; Engineering management; Industrial engineering; Monitoring; Probability density function; Process control; Technology management; Markov chain; average run length (ARL); exponentially weighted moving average (EWMA) chart; weighted variance (WV) method;
Conference_Titel :
Management Science and Engineering, 2007. ICMSE 2007. International Conference on
Conference_Location :
Harbin
Print_ISBN :
978-7-88358-080-5
Electronic_ISBN :
978-7-88358-080-5
DOI :
10.1109/ICMSE.2007.4421903