In #6, there was a wrapper added to perform the extraction. However, we extracted a bit too many terms. In particular, we only want to extract elements corresponding to the random-effects, not all effects (p). c.f.

Consider revising given:

Issue arose with:

m <- lmer(DV ~ P + P:H + (1+P||id), data = data)

No data was given, so an equivalent test case should be:

fm1 <- lmer(Reaction ~ Days + (1+Days || Subject), data = sleepstudy)