Dear Remi, On Wed, 17 Apr 2013 08:23:07 -0700 (PDT) Rémi Lesmerises <remilesmeri...@yahoo.ca> wrote: > Dear John, > > Thanks for your comments! But when I tried your suggestion, the output was as > the following: > > > Response Dist_arbre : > Df Sum Sq Mean Sq F value Pr(>F) > Poids 1 0.00010398 0.00010398 6.2910 0.0364733 * > Age 1 0.00005202 0.00005202 3.1476 0.1139652 > --- > Signif. codes: 0 *** 0.001 ** 0.01 * 0.05 . 0.1 1 > > I have the P-value but not the direction of the relationship, information > that I had with "lm(as.matrix(Y) ~ x+z)". I could combine the results of > these two tests, but it seems inelegant to me. Moreover I didn't have a total > significance test as with a true MANCOVA. > > An idea?!
Yes, try what I suggested. The output that you show here isn't from the the Anova() function in the car package. As well, you might find it useful to read the on-line appendix on multivariate linear models, at <http://socserv.socsci.mcmaster.ca/jfox/Books/Companion/appendix/Appendix-Multivariate-Linear-Models.pdf>, from the book with which the car package is associated. Best, John > > Rémi Lesmerises, biol. M.Sc., > Candidat Ph.D. en Biologie > Université du Québec à Rimouski > 300, allée des Ursulines > remilesmeri...@yahoo.ca > > > > ________________________________ > De : John Fox <j...@mcmaster.ca> > À : Rémi Lesmerises <remilesmeri...@yahoo.ca> > Cc : "r-help@r-project.org" <r-help@r-project.org> > Envoyé le : mercredi 17 avril 2013 10h54 > Objet : Re: [R] Mancova with R > > > Dear Remi, > > Take a look at the Anova() function in the car package. In your case, you > could use > > Anova(lm(as.matrix(Y) ~ x + z)) > > or, for more detail, > > summary(Anova(lm(as.matrix(Y) ~ x + z))) > > I hope this helps, > John > > ------------------------------------------------ > John Fox > Sen. William McMaster Prof. of Social Statistics > Department of Sociology > McMaster University > Hamilton, Ontario, Canada > http://socserv.mcmaster.ca/jfox/ > > On Wed, 17 Apr 2013 07:47:27 -0700 (PDT) > Rémi Lesmerises <remilesmeri...@yahoo.ca> wrote: > > Dear all, > > > > I'm trying to compare two sets of variables, the first set is composed > > exclusively of numerical variables and the second regroups factors and > > numerical variables. I can't use a Manova because of this inclusion of > > numerical variables in the second set. The solution should be to perform a > > Mancova, but I didn't find any package that allow this type of test. > > > > I've already looked in this forum and on the net to find answers, but the > > only thing I've found is the following: > > > > > > lm(as.matrix(Y) ~ x+z) > > x and z could be numerical and factors. The problem with that is it > > actually only perform a succession of lm (or glm), one for each numerical > > variable contained in the Y matrix. It is not a true MANCOVA that do a > > significance test (most often a Wald test) for the overall two sets > > comparison. Such a test is available in SPSS and SAS, but I really want to > > stay in R! Someone have any idea? > > > > Thanks in advance for your help! > > > > Rémi Lesmerises, biol. M.Sc., > > Candidat Ph.D. en Biologie > > Université du Québec à Rimouski > > remilesmeri...@yahoo.ca > > > > [[alternative HTML version deleted]] > > ------------------------------------------------ John Fox Sen. William McMaster Prof. of Social Statistics Department of Sociology McMaster University Hamilton, Ontario, Canada http://socserv.mcmaster.ca/jfox/ ______________________________________________ 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.
