hi everybody this is my last chance, I dont know what else to do I was trying to find my multiple comparisons using the code in R glht next is my function and the error I get vol.interallaovsol<-aov(scoresol~ffjob+ffage+ffstudies+ffjob:ffstudies+ffjob:ffage+ffstudies:ffage+ffjob:ffage:ffstudies,data=vol18.df)> vol.mcsol<-glht(vol.interallaovsol, linfct=mcp(ffage="Tukey"))Warning messages: 1: In mcp2matrix(model, linfct = linfct) : covariate interactions found -- default contrast might be inappropriate 2: In glht.matrix(model = list(coefficients = c(4.83, -0.884666666666668, : 157 out of 210 coefficients not estimable in ?model? I dont have a clue what is this. Any idea??thanksssssssssssssssssssss -- View this message in context: http://r.789695.n4.nabble.com/error-in-comparisons-using-glht-function-tp4648467.html Sent from the R help mailing list archive at Nabble.com.