I've been working on a GLMM in R and I see that an assumption of the test is that the random factor must be normally distributed (that is, unless you're using a package like
hglm where you can specify a different distribution). However, I can't find any sort of code for how to test the distribution of the random effect, does anyone here have any ideas?
I'm only aware of how to test the residuals of the GLMM for normality, via:
resid <- residuals(model) qqnorm(resid) qqline(resid, col = 2)
shapiro.test(residuals(model, type = "normalized"))