Re: [R] Nonparametric Effect size indices Martin PlÃ¶derl wrote: > Hello! >  > For comparing two non-normally distributed samples, Leech (2002) suggested > to report nonparametric effect size indices, such as Vargha & Delaney's A or > Cliff's d. I tried to search the R-sites, but could not find related > procedures or packages that include nonparametric effect sizes.  > Thank you for your help! >  > Citation: Leech (2002). A call for greater use of nonparametric statistics. > Paper presented at the Annual Meeting of the Mid-South Educational Research > Association, Chattanooga, TN, November 6-8.   Based on the description of Cliff's d in http://www.florida-air.org/romano06.pdf, you could do something like the following: g1 <- c(1,1,2,2,2,3,3,3,4,5) g2 <- c(1,2,3,4,4,5) # Dominance matrix sign(outer(g1, g2, FUN="-"))       [,1] [,2] [,3] [,4] [,5] [,6]  [1,]    0   -1   -1   -1   -1   -1  [2,]    0   -1   -1   -1   -1   -1  [3,]    1    0   -1   -1   -1   -1  [4,]    1    0   -1   -1   -1   -1  [5,]    1    0   -1   -1   -1   -1  [6,]    1    1    0   -1   -1   -1  [7,]    1    1    0   -1   -1   -1  [8,]    1    1    0   -1   -1   -1  [9,]    1    1    1    0    0   -1 [10,]    1    1    1    1    1    0 mean(rowMeans(sign(outer(g1, g2, FUN="-")))) [1] -0.25   If you can point us to a description of Vargha & Delaney's A, someone can likely suggest a way of obtaining that too. > Regards,  >  > Martin PlÃ¶derl PhD > Suicide Prevention Research Program, Institute of Public Health > Paracelsus Private Medical University > Dept. of Suicide Prevention, University Clinic of Psychiatry and > Psychotherapy > Christian - Doppler - Klinik > Ignaz Harrerstrasse 79 > A-5020 Salzburg > AUSTRIA > Phone: +43-662-4483-4345 > Fax: +43-662-4483-4344 > E-mail: M.Ploederl@salk.at >  > ______________________________________________ > R-help@stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code.  --  Chuck Cleland, Ph.D. NDRI, Inc. 71 West 23rd Street, 8th floor New York, NY 10010 tel: (212) 845-4495 (Tu, Th) tel: (732) 512-0171 (M, W, F) fax: (917) 438-0894 ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.