matrix factorization?
I think ALS is very applicable here. I would imagine it would need to be fine tuned quite a bit though. Unless the questions are correlated, it might yield some weird results. Just because two people with PHD's have one child, does not mean the third would only have one child. Basically, the more the data the better. Recommending movies works so well because all the columns are related to movies, but this should work with enough data.