Title: Using Exponentially Weighted Moving Average Charts
Author: Keith M. Bower
Publication Source: Asia Pacific Process Engineer, October 2000
Abstract
This paper investigates the Exponentially Weighted Moving Average (EWMA) control chart. After discussing some theory behind the EWMA chart, an example of using this statistical procedure is used.
Notes
In hindsight, I would have preferred using an example involving a system involved an exponentially increasing (or decreasing, e.g. tool wear) response, which the EWMA charting procedure is very useful for detecting. Instead, I employed a more “basic” small but sustained shift, which this procedure can still be effective at detecting.
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