Hi all This is probably a simple problem but somehow I am having much trouble with finding a solution, so I seek your help! I have a data-set with continuous response variables. The explanatory variably is 4xpH treatments (so 8.08, 7.94, 7.81 and 7.71) so also continuous and not technically factorial. However I have decided to do Anova's (as well as regression) to explore the effect of pH. What I don't understand is why the anova done in such a way: summary(aov(BioMass~pH)) ... gives me completely different p-values if I define the pH as factor or not. And what would be the correct approach? Help on this subject would be much appreciated! Hronn -- View this message in context: http://r.789695.n4.nabble.com/ANOVA-define-as-factor-or-not-tp3846861p3846861.html Sent from the R help mailing list archive at Nabble.com.
ANOVA define as factor or not
3 messages · HronnE, Jean V Adams
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Thank you very much for a quick reply! I had not realized the degrees of freedom changed. It was my lack of understanding of the "aov" function. I will continue defining the pH as factor for the ANOVA's. Cheers, Hronn -----
Hr?nn Egilsd?ttir PhD Student Marine Research Institute Sk?lagata 4 121 Reykjav?k ICELAND -- View this message in context: http://r.789695.n4.nabble.com/ANOVA-define-as-factor-or-not-tp3846861p3847781.html Sent from the R help mailing list archive at Nabble.com.