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  • 1 Post By chiro

Math Help - SD!

  1. #1
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    SD!

    guys take a look at this question:

    If A has 25 items with average of 100. B has 30 items of which 25 of it has same average as A. the remaining 5 is equal to 100.
    thus
    B = A, 100,100,100,100,100

    will they have same SD or not?

    my response is they will have different SD. pls any prove why am wrong here.

    thanks
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  2. #2
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    Re: SD!

    Hey lawochekel.

    Without more information, you can't conclude whether the standard deviations (or standard errors) are the same or not.
    Thanks from lawochekel
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  3. #3
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    Re: SD!

    what other information needed to decide whether the SD is the same or not?
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  4. #4
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    Re: SD!

    You need either the underlying distribution, a sample (of which you estimate the standard error) or the actual value itself.
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