Dear Stata list,

I'm having trouble registering my imputed variables, for a pairwise analysis; my understanding is that the code should be ~

Code:
mi set mlong
mi register imputed q1-q33
mi impute mvn q1-q33, emonly

matrix cov_pairwise = r(Sigma_em)
matrix list cov_pairwise
However, after the second line of code, I get the following error message:

Code:
. mi register imputed q1-q33
_mi_m not found
r(111);
My understanding is that on the mi set mlong, command, stata should create 3 new variables (_mi_miss, _mi_m, and _mi_id), but this doesn't seem to be happening.

Any advice as to how I might be able to solve this would be so greatly appreciated. Thanks for your consideration.

William