The Average Run Length and Detecting Process Shifts


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Thanks so much for reading our publication. We hope you find it informative and useful. Happy charting and may the data always support your position.

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BPI Consulting, LLC

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Comments (4)

  • Raphy BarSeptember 20, 2021 Reply

    I belive thre is a typo error: the mshif is +1sigma and +2sigma.The following exerpt:”The probability of getting a point beyond the mean + 2σ for the shifted process is:a = 1 – NORM.S.DIST(2, TRUE) = .02275″is correct for +1sigma.

    • billSeptember 20, 2021 Reply

      I believe the article is correct.  If a process shifts +1 sigma, the "new" 2 sigma is where the "old" 3 sigma was.  So, you are looking at the area above +2 sigma, which is 0.02275.

  • AnonymousDecember 27, 2021 Reply

    good

  • GerrohardtApril 21, 2022 Reply

    Thanks, good introduction to ARL

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