visreg() can usually find the data and parse the formula in order to identify the variables, but perhaps there should be an option so that the user can specify this for difficult/nonstandard packages (e.g., MuMIn when used with random effects models).
visreg()
can usually find the data and parse the formula in order to identify the variables, but perhaps there should be an option so that the user can specify this for difficult/nonstandard packages (e.g., MuMIn when used with random effects models).