Sampling Plan based on the Exponentially Weighted Moving Average Yield Index for Autocorrelation within Linear Profiles

Recently, the exponentially weighted moving average (EWMA) statistic has been applied to acceptance sampling plans. The advantage of EWMA statistic is to consider the quality of the current lot and the preceding lots. As the smoothing parameter value equals to one, the sampling plan based on the EWMA statistic becomes a single sampling plan. In this study, we propose a sampling plan based on the EWMA yield index for lot sentencing for autocorrelation within linear profiles. The plan parameters are determined by considering the acceptable quality level at the producer's risk and the lot tolerance percent defective at the consumer's risk. The plan parameters are tabulated for various combinations of the smoothing constant of EWMA statistic and the acceptable quality level and lot tolerance percent defective at two risks. An example is provided for illustrating the proposed plan. Copyright © 2015 John Wiley & Sons, Ltd.