Possible bug
Take a look at: xtabs(~Plant+Treatment, data=CO2) It appears to me that Plant incorporates both plant and treatment for use in a mixed model context. If you notice, Treatment is not completely ignored in the second version. The DF=11 for plant whereas in the first analysis it is 10 and there is 1 for Treatment. I may be wrong, but that is my guess.
On Mar 17, 2022, at 10:17 AM, konrad via R-help <r-help at r-project.org> wrote: Dear all, I recently conducted aov calculations of datasets::CO2. When I'm using the following code: 'summary(aov(CO2$uptake~CO2$Treatment*CO2$Plant))'. Everything is fine. I get a result for Plant and Treatment. However, if using: 'summary(aov(CO2$uptake~CO2$Plant*CO2$Treatment))' 'Treatment' is ignored. I'm using R 3.6 on Linux Mint. Any idea why this happens? Regards, Konrad
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