You wrote: > What's the difference between t.test(x, y) and pairwise.t.test()? Is > it just that the former takes two vectors, whereas the latter takes a > vector and a factor?
No. The pairwise.t.test() function (according to the help file) does a multiplicity of t-tests, on more than two samples, adjusting the p-value to compensate for the multiplicity by various methods. IMHO the name of this function is bad, because to me it suggests doing ***paired*** t-tests, which would trip up the naive user, who probably wouldn't notice or would ignore the "t tests with pooled SD" message in the output. As one of the Ripley fortunes says ``It really is hard to anticipate just how silly users can be.'' But why go out of the way to give them a chance to be silly? cheers, Rolf Turner [EMAIL PROTECTED] ______________________________________________ [EMAIL PROTECTED] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html