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how to do normality test in excel
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how to do normality test in excel
You should always include body text in your post, not just an
informative subject line. Some web based news servers do not permit replies to posts that have no body. Excel has no built-in tests for Normality, but it also is not a statistical package (it is a spreadsheet that has some limited statistical capabilities built in). The usual quantitative tests, such as Shapiro-Wilk would require that you insert tabled values http://www.itl.nist.gov/div898/handb...on2/prc213.htm or use a commercial Add-In such as http://www.analyse-it.com/shapiro-wi...ity-test_y.htm If you don't mind translating Fortran, then you might look at http://lib.stat.cmu.edu/apstat/R94 You could do a rough and ready chi-square test, by dividing the real line into a n intervals, each having an expected value under normality of at least 5 observations with your sample size. Then sum (Observed-Expected)^2/Expected and compare to CHIINV(alpha,n-1) where alpha is suitably small (say 0.05) Qualitatively, you could plot the data as a histogram and observe whether it looks roughly bell-shaped. A more discriminating qualitative approach would be to do a normal probability plot. Mike Middleton has a downloadable paper on this at http://www.usfca.edu/~middleton/data.htm If you want a full-blown statistics package, R is free www.r-project.org Jerry |
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