IDEAS home Printed from https://ideas.repec.org/a/taf/lstaxx/v51y2022i14p4617-4637.html
   My bibliography  Save this article

Variable sampling interval EWMA chart for multivariate coefficient of variation

Author

Listed:
  • Heba N. Ayyoub
  • Michael B. C. Khoo
  • Sajal Saha
  • Ming Ha Lee

Abstract

A control chart for monitoring the multivariate coefficient of variation (MCV) is used when the focus is on monitoring the ratio of relative multivariate variability to the mean of a multivariate process. The MCV chart is useful in process monitoring when practitioners are not interested in the consistency of the mean vector or covariance matrix. This study proposes a one-sided upward variable sampling interval (VSI) exponentially weighted moving average (EWMA) chart to detect increasing shifts in MCV squared (γ2) and shows the derivation of formulae to evaluate the performance of the VSI EWMA-γ2 chart by using the Markov chain approach. Comparative investigations show that the proposed chart outperforms existing MCV charts in detecting shifts in process MCV. A numerical example that uses real data reveals that the proposed chart performs well in actual applications.

Suggested Citation

  • Heba N. Ayyoub & Michael B. C. Khoo & Sajal Saha & Ming Ha Lee, 2022. "Variable sampling interval EWMA chart for multivariate coefficient of variation," Communications in Statistics - Theory and Methods, Taylor & Francis Journals, vol. 51(14), pages 4617-4637, July.
    • Handle: RePEc:taf:lstaxx:v:51:y:2022:i:14:p:4617-4637
    DOI: 10.1080/03610926.2020.1818100
    as

    Download full text from publisher

    File URL: http://hdl.handle.net/10.1080/03610926.2020.1818100
    Download Restriction: Access to full text is restricted to subscribers.
    File URL: https://libkey.io/10.1080/03610926.2020.1818100?utm_source=ideas
    LibKey link: if access is restricted and if your library uses this service, LibKey will redirect you to where you can use your library subscription to access this item
    ---><---

    As the access to this document is restricted, you may want to search for a different version of it.

    More about this item

    Statistics

    Access and download statistics

    Corrections

    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:taf:lstaxx:v:51:y:2022:i:14:p:4617-4637. See general information about how to correct material in RePEc.

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    We have no bibliographic references for this item. You can help adding them by using this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: Chris Longhurst (email available below). General contact details of provider: http://www.tandfonline.com/lsta .

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service. RePEc uses bibliographic data supplied by the respective publishers.