Computing and summarizing contrasts from brmsfit

[torkar]

Hi and welcome to the community!

Have you checked this? I usually do it as in the second post below (@bgoodri’s reply).

Contrast coding with brms

It seems that brm() adopts the the default settings in R: factors (categorical variables) are dummy-coded with 0/1. If I want to switch to deviation coding (-1, 0, and 1), would adding the following line in R work? options(contrasts = c(“contr.sum”, “contr.poly”)) Thanks!

Contrasts in BRMS

Hi all, I have read for long time passively here but now I have 2 questions. I am confused about how to present group differences when I fit a model like e.g. this: y ~ factorA * factorB + factorC*factorD + continuous_variable_s When using lme4 or just the built in lm function in R, I needed to apply contr.sum to each factor because otherwise the comparison would be made to one reference group that might not be the comparison I need. But I always found this confusing and difficult to interpre…