HI, May be the below links help: http://r.789695.n4.nabble.com/TukeyHSD-troubles-td1570205.html http://r.789695.n4.nabble.com/TukeyHSD-error-td3051059.html
A.K. Hi I'm trying to run a Tukey test on mortality data, where I want to test whether mortality is influenced by the amount of copper (in an one-way ANOVA) and the combination of copper and temperature (in a two-way ANOVA). These are my formulas: lm2<-lm(Mortality~Cu) anova(lm2) TukeyHSD(aov(Mortality~Cu)) lm2<-lm(Mortality~Cu+Temp+Cu:Temp) anova(lm2) TukeyHSD(aov(Mortality~Cu+Temp+Cu:Temp)) The ANOVA is no problem, but for both Tukey's, I get the following error message: Error in TukeyHSD.aov(aov(Mortality ~ Cu + Temp + Cu:Temp)) : no factors in the fitted model In addition: Warning messages: 1: In replications(paste("~", xx), data = mf) : non-factors ignored: Cu 2: In replications(paste("~", xx), data = mf) : non-factors ignored: Temp 3: In replications(paste("~", xx), data = mf) : non-factors ignored: Cu, Temp I've read on other posts that there should be a factor somewhere, but all my data are numbers! I'm quite baffled and have no idea what to do next. Thanks in advance for your help! Lundill ______________________________________________ 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.