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Homework Help: Statistics: sample median, means, s.d. vs sample size

  1. Oct 23, 2005 #1
    i have a set containing 10000 data. i took 1000 samples of size 4, 16, 64, and 1024 and took the medians, means, and stadard deviations of each size. i graphed them sd of medians vs sample size, sd of mean vs sample size, and sd of s.d. vs sample size. for sample mean, i know from a text book that:
    SD of sample means = population SD / sqrt(sample size n).
    But it seems from the graph i created using R, sd of medians and s.d. vs sample size all have the exact same looking graph, which to me suggests that:
    SD of sample means, medians, and s.d. = population SD / sqrt(sample size n).
    Is this right? it seems a little awkward. any input will be very helpful. thank you
     
  2. jcsd
  3. Oct 24, 2005 #2

    EnumaElish

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    What is R?

    More generally, is your question whether the "sample vs. population" formula (sample stat = population stat/sqrt(n)) applies to median and std. dev. in addition to the mean?
     
  4. Oct 25, 2005 #3
    R is just a program language kind of like matlab.

    "More generally, is your question whether the "sample vs. population" formula (sample stat = population stat/sqrt(n)) applies to median and std. dev. in addition to the mean?"

    This is exact what i'm asking.
     
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