[R] ANOVA Residual SS and MS of 0

I am trying to run an ANOVA on my soil respiration data, but I keep getting residual sum of squares and mean square of zero. As I understand it that would mean that the model terms explain all of the variation in the response variable. That should be virtually impossible, should it not? Where do

Re: [R] ANOVA 1 too few degrees of freedom

Please read the first two paragraphs of Details from ?formula Ok, I just did. So, If I understand this properly, the term Plot*Day would include both the main effects of a and b and their second order interactions. So it could be written Plot + Day + Plot:Day. The term Plot:Day includes only

Re: [R] ANOVA 1 too few degrees of freedom

So what is the difference between a colon and an asterisk in this code? For that matter what does the slash mean? -- View this message in context: http://r.789695.n4.nabble.com/ANOVA-1-too-few-degrees-of-freedom-tp3493349p3512977.html Sent from the R help mailing list archive at Nabble.com.

Re: [R] ANOVA 1 too few degrees of freedom

Thanks slre, I seem to be making some progress now. Using a colon instead of an asterisk in the code really changes things. I had been getting residual SS and MS of zero. Which is ridiculous. Now I get much more plausible values. Also, When I used an asterisk instead of a colon It wouldn't give

Re: [R] ANOVA 1 too few degrees of freedom

And I responded as follows: Hi, Thanks for your advice. I tried using table() to check for missing data. Here are the results: > table(Combined.Plot) Combined.Plot 60m A1 B1 B3 B4 C5 C9 D2 D9 F60m F8 Q7 34 34 3434 343434 3434 34 34 34 >

Re: [R] ANOVA 1 too few degrees of freedom

This response went to my email: Without your data it's hard to say, but one possibility is that your plots are nested within treatments instead of crossed, or that you have something rather more cunning going on involving the Days. For example if you had 8 days for six of your plots and another 8

Re: [R] ANOVA 1 too few degrees of freedom

Hi Richard, Thanks for your advice. I think that your suggestion is that I run the ANOVA with Combined.Plot as a factor. I have tried that does not alleviate the problem. Did I understand you properly? Do you have another idea? Thanks, David -- View this message in context: http://r.789695.

[R] ANOVA 1 too few degrees of freedom

I'm running an ANOVA on some data for respiration in a forest. I am having a problem with my degrees of freedom. For one of my variables I get one fewer degrees of freedom than I should. I have 12 plots and I therefore expected 11 degrees of freedom, but instead I got 10. Any ideas? I have some