I want to translate this formula from
glmer() (lme4 package) to
glmmPQL() (MASS package).
glmer(y ~ a + b + c + (a + b + c | x), family = binomial())
I want to include the random intercept and the random slopes of all 3 predictors (
c) in my model.
I have tried this one (not sure whether I rewrote the formula correctly), but it seems not working.
glmmPQL(y ~ a + b + c, random = ~ a + b + c | x, family = binomial())
Here is the error message. Not exactly sure whether it was a formula error or convergence error.
Error in lme.formula(fixed = y ~ 1 + a + b + c, random = ~1 + : nlminb problem, convergence error code = 1 message = iteration limit reached without convergence (10)