On Sun, 2005-12-25 at 23:01 -0300, Petra Wallem wrote: > Hello every body, I am trying to do a factorial anova analysis > following this model: > > model<-anova(lm(responsevariable~factorA*factorB)) > model<-anova(lm(luz$dosel~luz$estado*luz$Bosque)) > > Df Sum Sq Mean Sq F value Pr(>F) > estado 1 6931.1 6931.1 41.6455 7.974e-06 *** > Bosque 1 36.6 36.6 0.2197 0.6456 > estado:Bosque 1 36.6 36.6 0.2197 0.6456 > Residuals 16 2662.9 166.4 > > Strange is that the sum of squares of the factor Bosque are identical to > the SS of the interaction, and are non significant. But when I plot the > data, the interaction surley is significant... > > my data.frame looks as follows: > > Bosque estado lux dosel > 1 deciduo pristino 703 88.56 > 2 deciduo pristino 800 90.64 > 3 deciduo pristino 150 95.84 > 4 deciduo pristino 245 87.52 > 5 deciduo pristino 1300 91.68 > 6 deciduo activo 1900 26.16 > 7 deciduo activo 840 59.44 > 8 deciduo activo 323 69.84 > 9 deciduo activo 112 75.04 > 10 deciduo activo 1360 51.12 > 11 siemprev activo 900 41.76 > 12 siemprev activo 480 65.68 > 13 siemprev activo 350 78.16 > 14 siemprev activo 350 37.60 > 15 siemprev activo 272 58.40 > 16 siemprev pristino 100 94.80 > 17 siemprev pristino 60 95.84 > 18 siemprev pristino 50 97.92 > 19 siemprev pristino 270 94.80 > 20 siemprev pristino 110 97.92 > > Dose some body understand what I am doing wrong??? I have been > navigating at the R site search, but didn't found much posting on > factorial anova. > > In advance thanks a lot for your comments > Petra > > ______________________________________________ > R-help@stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
It would help if you would use the "dump" function and paste the output into an e-mail: > dump("luz","") Also, it's much easier to use "data=luz" as an argument in the lm function rather than appending the data frame name to each variable. I don't think that "model" contains the lm model output. It looks like you are saving the anova table. ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html