Using exponentially weighted moving average (EWMA) charts
نویسندگان
چکیده
1. Unlike X -R and Individuals charts (without the Western Electric Handbook rules which aim to increase sensitivity), all of the data collected over time may be used to determine the control status of a process. 2. The EWMA is often superior to the CUSUM charting technique for detecting "larger" shifts. 3. EWMA schemes may be applied for monitoring standard deviations in addition to the process mean. 4. There exists the ability to use EWMA schemes to forecast values of a process mean. 5. The EWMA methodology is not sensitive to normality assumptions.
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