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Thread: PLease, help, t-test or something else? And how :)

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    PLease, help, t-test or something else? And how :)




    HI!

    I have a huge problem. Those are my results from experiments: animals which ate water *i.e. control group) has these value for amount of enzymes:
    1857
    6218
    5114
    6972
    1820
    4237
    Animals which ate food (ie test group has these values:
    1859
    2277
    2260
    3847
    1632
    17155

    I checked for outliers and 17155 i excluded.

    So, my mail concern is which t test would be appropriate?

    I expect that enzymes are increased if animals ate food, but if I remove outlier (17155 in test group, 6972 in control group is very close, but not outlier yet ) then mean is lower in treated than in control group. By two tailed t test there is no difference, but by one tailed there is difference, and from that point it is absurd because it means that test group has LOWER amount, and common sense says it should be higher.
    The same thing is happening no matter whether I use Welch correction or not.
    Please, any advice, help or suggestion?

    Thanks a lot.

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    Re: PLease, help, t-test or something else? And how :)

    Is there any way to learn more about the outlier?

    Also - have you considered the possibility that your common sense is just completely wrong?
    I don't have emotions and sometimes that makes me very sad.

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    Re: PLease, help, t-test or something else? And how :)


    outlier was checked by grubbs test (and that animal wasnt quite happy during experiment).

    and I am considering that my common sense might be completely wrong, but for me is seems that that is not the case in this situation.

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