Stefan Th. Gries <stgries <at> gmail.com> writes: > > Hi all > > I have a question regarding the Fligner-Killeen test. I am using > > - a PC with Windows XP (Build 20600.xpsp080413-2111 (Service Pack 3); > - the following R version: > > sessionInfo() > R version 2.7.0 (2008-04-22) > i386-pc-mingw32 > > I have a vector LENGTH and a factor RELATION that are distributed like this: > > > table(LENGTH, RELATION) > RELATION > LENGTH object subject [snip] > > fligner.test(LENGTH[RELATION=="subject"], LENGTH[RELATION=="object"]) > Fligner-Killeen test of homogeneity of variances > data: LENGTH[RELATION == "subject"] and LENGTH[RELATION == "object"] > Fligner-Killeen:med chi-squared = 18.3552, df = 14, p-value = 0.1911 > > > fligner.test(LENGTH[RELATION=="object"], LENGTH[RELATION=="subject"]) > Fligner-Killeen test of homogeneity of variances > data: LENGTH[RELATION == "object"] and LENGTH[RELATION == "subject"] > Fligner-Killeen:med chi-squared = 16.8838, df = 13, p-value = 0.2047 > > > fligner.test(LENGTH~RELATION) > Fligner-Killeen test of homogeneity of variances > data: LENGTH by RELATION > Fligner-Killeen:med chi-squared = 0.626, df = 1, p-value = 0.4288 > ######### > > The order of the vectors etc. changes the results??? Needless to say > this does not happen with var.test or ... Is this normal; if so, which > one is the one to report?
I think you misunderstood the manual page for fligner.test. I believe that all of the following should give identical results (corresponding to the last test in your examples): fligner.test(list(LENGTH[RELATION=="subject"], LENGTH[RELATION=="object"])) fligner.test(list(LENGTH[RELATION=="object"], LENGTH[RELATION=="subject"])) fligner.test(LENGTH,RELATION) fligner.test(LENGTH~RELATION) ______________________________________________ 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.
