On 10/23/2009 1:30 PM, slrei...@vims.edu wrote: > Hello- > I have run an ANOVA on 4 treatments with unequal sample sizes (n=9,7,10 > and 10). I want to determine where my sig. differences are between > treatments using a Bonferroni test, and have run the code: > > pairwise.t.test(Wk16, Treatment, p.adf="bonf") > > I receive an error message stating that my arguments are of unequal length: > > Error in tapply(x, g, mean, na.rm = TRUE) : > arguments must have same length > > Is there a way to run this test even with unequal sample sizes?
Unequal sample sizes are not causing the reported error. The problem is that 'Wk16' and 'Treatment' do not have the same number of observations. If the group sizes are 9, 7, 10, and 10, then 'Wk16' and 'Treatment' should each contain 36 observations. > Thanks. > Stephanie Reiner > Andrews Hall 410 > Shipping: Rt. 1208 Greate Road > Gloucester Point, VA 23062 > work: 804-684-7869 > cell: 443-286-4795 > > ______________________________________________ > R-help@r-project.org 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. (www.ndri.org) 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@r-project.org 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.
