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    hey, I always forget how to determine the skewness in a distribution and I was wondering if anyone has a way to remember this topic. I think i missed a lesson on it, so I don't have any notes to help. thank you for your time!
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    (Original post by theguywhosaidhi)
    hey, I always forget how to determine the skewness in a distribution and I was wondering if anyone has a way to remember this topic. I think i missed a lesson on it, so I don't have any notes to help. thank you for your time!
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    Bizarrely, I hold my hand out like so (that is my hand...) and then remember that if more < median < mean, then there is a positive skew.

    Yes, there is no logic to that or anything that makes it memorable apart from the hand making the less than sign to give me positive but it's how I've remembered it.

    Then negative skew is just keeping the terms in place and flipping the signs, so mode>median>mean for negative skew.

    Though I read somewhere that in reality statisticians don't use the mode to compare it..

    The other two things are a box plot, where you look at the line for the median and determine whether it's closer to the LQ or the UQ.

    Then using the first measure, if the median is closer to the LQ then the mean will be greater than the median as the median is teaively low so the mean will be somewhere to the right of the median line. Then opposite for negative skew.

    You can also use the quartiles.. and a calculation involving mean and median and standard deviation... but best to find this chapter in your book and practice questions, that's the best way of remembering it.
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    (Original post by theguywhosaidhi)
    hey, I always forget how to determine the skewness in a distribution and I was wondering if anyone has a way to remember this topic. I think i missed a lesson on it, so I don't have any notes to help. thank you for your time!
    I personally have always regarded the mean as my favourite type of average, so to me the mean being the biggest (read: best) was a positive/good thing.

    mean is biggest = mean is best = positive skew

    Just come up with something silly to remember it, it doesnt have to make sense
 
 
 
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