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Hypothesis Testing Roadmap – Pocket Guide

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This topic contains 2 replies, has 3 voices, and was last updated by  Robert Butler 2 months, 3 weeks ago.

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  • #56072

    Boyan Angelov
    Participant

    Hi All,

    I stumbled upon this hypothesis testing guide a month ago , and since then I keep it on my desktop as reference.
    I think it may be useful to others as well.

    Kind regards,
    Boyan

    #202945

    Deglis Fernando
    Participant

    Wonderful.

    Very useful!

    Best Regards,

    #202994

    Robert Butler
    Participant

    It’s nice but it has a number of faults and it places restrictions where none exist.

    1. The decision tree for variable data normal yes/no is wrong. Both the t-test and ANOVA are robust with respect to non-normal data so the roadmap with respect to these test is wrong. The roadmap does correctly identify the fact that Bartlett’s test is very sensitive to non-normality unfortunately it implies that Levene’s test should not be used with normal data – which is wrong. Levene’s test can handle normal or non-normal data and it is for this reason that it is the test used by statisticians – I don’t know of anyone in the field who uses or recommends Bartlett’s test anymore.

    2. The decision tree for X > 1 is just plain wrong. You can use any of the methods on the left side of that diagram when there is only one X. Whether you choose to use logistic/multinomial regression or some kind of MxN chi-square table to address a problem with respect to attribute data will depend on what it is that you want to know.

    3. The warning about unequal variances and “proceed with caution” in the lower left and lower right boxes is nice but it is of no value – in particular it does not tell you what to do or how to check to see if the existence of unequal variances matters.

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