On 8/14/2009 10:06 AM, Casimir wrote: > Hi! > > I am quiet new with R and I have some problems to perform a posthoc test > with an lme model. > My model is the following: > >> lme1<-lme(eexp~meal+time, random=~1|id,na.action=na.omit) > > and then i try to get a post hoc test: > >> summary(glht(lme1,linfct=mcp(meal="Tukey))) > > but I get a warning message: Erreur dans as.vector(x, mode) : argument > 'mode' incorrect > > Thank you for your help > > Guillaume
Use the data argument in the call to lme(). For example, this works: library(multcomp) library(nlme) Orthodont$AGECAT <- as.factor(Orthodont$age) fm1 <- lme(distance ~ AGECAT + Sex, data = Orthodont, random = ~ 1 | Subject) summary(glht(fm1, linfct=mcp(AGECAT = "Tukey"))) Simultaneous Tests for General Linear Hypotheses Multiple Comparisons of Means: Tukey Contrasts Fit: lme.formula(fixed = distance ~ AGECAT + Sex, data = Orthodont, random = ~1 | Subject) Linear Hypotheses: Estimate Std. Error z value Pr(>|z|) 10 - 8 == 0 0.9815 0.3924 2.501 0.05984 . 12 - 8 == 0 2.4630 0.3924 6.277 < 0.001 *** 14 - 8 == 0 3.9074 0.3924 9.958 < 0.001 *** 12 - 10 == 0 1.4815 0.3924 3.776 < 0.001 *** 14 - 10 == 0 2.9259 0.3924 7.457 < 0.001 *** 14 - 12 == 0 1.4444 0.3924 3.681 0.00123 ** --- Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1 (Adjusted p values reported -- single-step method) But this does not work and returns the error you got: attach(Orthodont) fm2 <- lme(distance ~ AGECAT + Sex, random = ~ 1 | Subject) summary(glht(fm2, linfct=mcp(AGECAT = "Tukey"))) Error in as.vector(x, mode) : invalid 'mode' argument -- 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.