Only detailed reviews. If you don’t know what the criteria are, they can easily be worse—counting as negative a factor you would consider positive, for example.
I would suggest that if you know nothing about the rating system, it is still likely to positively correlate because of universal factors like speaking clearly. In the case of RMP, I’d suggest that you’d expect an even better correlation because easiness and attractiveness are asked about separately. It’s still possible for this not to work out because of what you suggest, but it seems less likely to me on average.
Only detailed reviews. If you don’t know what the criteria are, they can easily be worse—counting as negative a factor you would consider positive, for example.
I would suggest that if you know nothing about the rating system, it is still likely to positively correlate because of universal factors like speaking clearly. In the case of RMP, I’d suggest that you’d expect an even better correlation because easiness and attractiveness are asked about separately. It’s still possible for this not to work out because of what you suggest, but it seems less likely to me on average.