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Minitab T-Charts Have Wrong Control Limits, Exponentially Distributed Data

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  • #246227

    Fausto Galetto
    Participant

    WHY Minitab Inc. Managment do not take suitable Corrective Actions about their

    “””MINITAB T Charts have WRONG Control Limits, Ewhen the data arexponentially Distributed”””?

    They have  been informed about the problem!!!!

    What is your opinion?

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    #246229

    Daniel Sims
    Participant

    Not this again. Don’t you have anything better to do??

    1
    #246230

    Fausto Galetto
    Participant

    Are you all very happy of this big drawback of MINITAB?

    0
    #246237

    David007
    Participant

    Fausto runs an IMR chart on exponentially distributed data and declares the process is out of control.  He must love those type I errors.

    Fausto makes proclamations about a process based on a sample size of 20.

    Fausto’s students search in vain for an assignable cause but there are none to be found because the process is inherently exponential.

    Fausto shouts from the rooftop “Minitab is wrong” “Six Sigma is a hoax” while Six Sigma practitioners just carry on doing what they have been doing for over 30 years, improving processes and saving money.

    • This reply was modified 1 month, 1 week ago by David007.
    1
    #246250

    Fausto Galetto
    Participant

    @David007

    You say:

    “””Fausto’s students search in vain for an assignable cause but there are none to be found because the process is inherently exponential.”””

     

    PROVE that if the data are “””inherently exponential””” there are NO Assignable causes!!!

     

    YOU forgot that T CHARTS Control Limits are WRONG in Minitab!!!!!!!!!!!!!!

    AND YOU forgot that T CHARTS Control Limits are WRONG in Minitab, NOT with Type I error, BUT > 95% of the times, as per YOUR request of SIMULATIONS!!!!!!!!!!!!!!

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    #246320

    Fausto Galetto
    Participant

    @Daniel.S 

    Continuous Improvement Engineer AND

    Lean Six Sigma Black Belt

    SHOULD WANT that MINITAB IMPROVE their ERRORS!!!

    WHY do you do not ask them to do that????????????????

    • I Don’t have anything better to do—————

     

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