A critique of the use of modified and moving average‐based EWMA control charts

We show that the so‐called modified exponentially weighted moving average (EWMA) control chart is very closely related to a moving average‐based EWMA chart. These charts have ill‐advised weighting functions that assign more weight to some past data values than to the most recent data values. We show...

Full description

Saved in:
Bibliographic Details
Published in:Quality and reliability engineering international 2023-06, Vol.39 (4), p.1269-1276
Main Authors: Haq, Abdul, Woodall, William H.
Format: Article
Language:English
Subjects:
conditional expected delay
Control charts
Monte Carlo simulation
process mean
run length distribution
statistical process monitoring
Weighting functions
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We show that the so‐called modified exponentially weighted moving average (EWMA) control chart is very closely related to a moving average‐based EWMA chart. These charts have ill‐advised weighting functions that assign more weight to some past data values than to the most recent data values. We show that these weighting functions adversely affect their run length properties and that one can obtain better overall performance with an ordinary EWMA chart.
ISSN:0748-8017
1099-1638
DOI:10.1002/qre.3290