Hi, I have two doubts about the nested aov output. 1) I have this:> anova.ratos <- aov(Glicogenio~Tratamento+Error(Tratamento/Rato/Figado)) > summary(anova.ratos)Error: Tratamento Df Sum Sq Mean Sq Tratamento 2 1557.56 778.78 Error: Tratamento:Rato Df Sum Sq Mean Sq F value Pr(>F) Residuals 3 797.67 265.89 Error: Tratamento:Rato:Figado Df Sum Sq Mean Sq F value Pr(>F) Residuals 12 594.0 49.5 Error: Within Df Sum Sq Mean Sq F value Pr(>F) Residuals 18 381.00 21.17 R dont make the F and P automatically, it is possible? I Like an output like this: Error: Tratamento Df Sum Sq Mean Sq F value Pr(>F) Tratamento 2 1557.56 778.78 2.929 0.197 Error: Tratamento:Rato Df Sum Sq Mean Sq F value Pr(>F) Residuals 3 797.67 265.89 5.372 0.0141 Error: Tratamento:Rato:Figado Df Sum Sq Mean Sq F value Pr(>F) Residuals 12 594.0 49.5 2.339 0.0503 Error: Within Df Sum Sq Mean Sq F value Pr(>F) Residuals 18 381.00 21.17 Why it not make automatic calculations? It is possible? 2) I can say that Error: Tratamento:Rato means an interaction between Tratamento and Rato? Normally the : represents an interaction, but in this output I think that it dont mean the interaction. Any explanation are welcome. Thanks Ronaldo -- O casamento ?? o caminho mais caro para se dormir com uma mulher. -- |> // | \\ [***********************************] | ( ?? ?? ) [Ronaldo Reis J??nior ] |> V [UFV/DBA-Entomologia ] | / \ [36570-000 Vi??osa - MG ] |> /(.''`.)\ [Fone: 31-3899-4007 ] | /(: :' :)\ [chrysopa at insecta.ufv.br ] |>/ (`. `'` ) \[ICQ#: 5692561 | LinuxUser#: 205366 ] | ( `- ) [***********************************] |>> _/ \_Powered by GNU/Debian Woody/Sarge
Others may know the answer to your question, but I don't. However, since I have not seen a reply, I will offer a few comments: 1. What version of R are you using? I just tried superficially similar things with the examples in ?aov in R 2.1.1 patched and consistently got F and p values. 2. My preference for this kind of thing is to use lme in library(nlme) or lmer in library(lme4). Also, I highly recommend Pinheiro and Bates (2000) Mixed-Effects Models in S and S-Plus (Springer). 3. If still want to use aov and are getting this problem in R 2.1.1, could you please provide this list with a small, self contained example that displays the symptoms that concern you? And PLEASE do read the posting guide! "http://www.R-project.org/posting-guide.html". It might increase the speed and utility of replies. spencer graves Ronaldo Reis-Jr. wrote:> Hi, > > I have two doubts about the nested aov output. > > 1) I have this: > >>anova.ratos <- aov(Glicogenio~Tratamento+Error(Tratamento/Rato/Figado)) >>summary(anova.ratos) > > > Error: Tratamento > Df Sum Sq Mean Sq > Tratamento 2 1557.56 778.78 > > Error: Tratamento:Rato > Df Sum Sq Mean Sq F value Pr(>F) > Residuals 3 797.67 265.89 > > Error: Tratamento:Rato:Figado > Df Sum Sq Mean Sq F value Pr(>F) > Residuals 12 594.0 49.5 > > Error: Within > Df Sum Sq Mean Sq F value Pr(>F) > Residuals 18 381.00 21.17 > > R dont make the F and P automatically, it is possible? > > I Like an output like this: > > Error: Tratamento > Df Sum Sq Mean Sq F value Pr(>F) > Tratamento 2 1557.56 778.78 2.929 0.197 > > Error: Tratamento:Rato > Df Sum Sq Mean Sq F value Pr(>F) > Residuals 3 797.67 265.89 5.372 0.0141 > > Error: Tratamento:Rato:Figado > Df Sum Sq Mean Sq F value Pr(>F) > Residuals 12 594.0 49.5 2.339 0.0503 > > Error: Within > Df Sum Sq Mean Sq F value Pr(>F) > Residuals 18 381.00 21.17 > > Why it not make automatic calculations? It is possible? > > > 2) I can say that Error: Tratamento:Rato means an interaction between > Tratamento and Rato? Normally the : represents an interaction, but in this > output I think that it dont mean the interaction. > > Any explanation are welcome. > > Thanks > Ronaldo-- Spencer Graves, PhD Senior Development Engineer PDF Solutions, Inc. 333 West San Carlos Street Suite 700 San Jose, CA 95110, USA spencer.graves at pdf.com www.pdf.com <http://www.pdf.com> Tel: 408-938-4420 Fax: 408-280-7915
Ronaldo , It looks as though you have specified you model incorrectly. In the Rats example ,the Treatment is the only fixed effect,Rat and Liver are random effects In aov testing for sig of 'Means' of Random Effects is pointless and that is why 'p' values are not given.Further more the interaction between a Random Effect and a Fixed Effect is also a Random Effect. The 'aov' with error structure terms output reflects this by only giving 'p' values to Fixed Effects and their interactions. Note That the Fixed Effects of Block, Variety and their interaction Block:Variety are given "p" values while the Field'Random Effects have not.> model <- aov(Glycogen~Treatment+Error(Rat/Liver)) > summary(model)Error: Rat Df Sum Sq Mean Sq F value Pr(>F) #Rat is random effect Residuals 1 413.44 413.44 Error: Rat:Liver #Rat:Liver is Random effect Df Sum Sq Mean Sq F value Pr(>F) Residuals 4 164.444 41.111 Error: Within Df Sum Sq Mean Sq F value Pr(>F) Treatment 2 1557.56 778.78 18.251 8.437e-06 *** #Fixed effect Residuals 28 1194.78 42.67 --- Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1 I hope that this is of help. John