[R-lang] ANOVA type main effects

[Xiao He]

Hi dear r-lang users,

I have a question about ANOVA type of main effects. From what I've read, one
way to obtain the type of main effect one would get with ANOVA is to do
model comparisons, like below:

mod1<-lmer(dv ~ iv1 + iv2 + (1|subject), data)
mod2 <-lmer(dv ~iv1 + (1|subject), data)
anova(mod1, mod2).

A significant difference indicates that the factor iv2 make significant
contribution to the model.

However, I wonder if there are other ways to obtain the same information.
Specifically, I have a 2X2 design, I wonder if, after I center the two
2-level factors, the results would be equivalent to ANOVA type of main
effects as opposed to simple effects. Thank you in advance!


Xiao
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