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Kolmogorov smirnov in r - cannot compute correct p-values with ties

  1. Jan 18, 2013 #1
    I'm trying to use the kolmogorov smirnov test in in R to compare one distribution with another. I'm getting the following error: cannot compute correct p-values with ties
    I think this is because the dataset that I am using has in the first instance around 2000 values, and the second, 50000 values. A number of these are inherently going to be replicates of another number in the series (i.e. "ties"). I'm just wondering if this has implcations for the p value I have? Is the p value valid?
    Cheers all
  2. jcsd
  3. Jan 19, 2013 #2

    Stephen Tashi

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    Science Advisor

    Did you read the R documentation for the ks.test function?

    You could test the sensitivity of the p-value empirically. Add small random perturbations to your data to generate new data sets that have more digits. See how much the p value changes.
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