check for missing values. Tal
On Wed, Sep 23, 2009 at 3:27 PM, pompon <julien.pom...@agr.gc.ca> wrote: > > Hi, > > I am performing a repeated measures 2-way ANOVA to assess the influence of > plant and leaf on aphid fecundity. Fecundity is measured for each aphid on > a > single leaf. > Here is what I typed. > > wingless <- reshape(Wingless, > varying = > > list(c("d0","d1","d2","d3","d4","d5","d6","d7","d8","d9","d10","d11","d12","d13","d14","d15","d16")), > v.names = c("fecundity"), timevar = "time", > direction = "long") > > wingless.aov <- aov(fecundity ~ factor(time) * clip.cage * plant + > Error(factor(id)), data = wingless) > > summary(wingless.aov) > > and I obtained > > Error: factor(id) > Df Sum Sq Mean Sq F value Pr(>F) > factor(time) 4 56.789 14.197 3.0613 0.05925 . > clip.cage 1 14.149 14.149 3.0509 0.10621 > plant 1 3.251 3.251 0.7010 0.41880 > factor(time):clip.cage 1 0.304 0.304 0.0655 0.80240 > clip.cage:plant 1 17.114 17.114 3.6903 0.07880 . > Residuals 12 55.652 4.638 > --- > Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1 > > Error: Within > Df Sum Sq Mean Sq F value Pr(>F) > factor(time) 16 340.83 21.30 11.5222 < 2e-16 *** > factor(time):clip.cage 16 27.34 1.71 0.9242 0.54195 > factor(time):plant 16 46.36 2.90 1.5673 0.07783 . > factor(time):clip.cage:plant 16 24.50 1.53 0.8281 0.65304 > Residuals 255 471.44 1.85 > --- > Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1 > > I don't understand why I have the factor(time) inmy between subject > results, > whereas with a similar set of data I don't. > > Thank you very much, > Julien Pompon. > -- > View this message in context: > http://www.nabble.com/repeated-measures-tp25531110p25531110.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > 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. > -- ---------------------------------------------- My contact information: Tal Galili Phone number: 972-50-3373767 FaceBook: Tal Galili My Blogs: http://www.r-statistics.com/ http://www.talgalili.com http://www.biostatistics.co.il [[alternative HTML version deleted]] ______________________________________________ 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.