IIP - Monster/Item Droprate Database

The pink conehat thing is just because the level requirement on them is much lower than the level of coldeyes. Chance of equipment dropping is generally based on the relation between the equipment's level req and the monster's level, with weapons, stars, and scrolls dropping much less frequently of course.

Is there data to back that up, or is that just an accepted "fact?" I've noticed similar correlations, but I was intending to base this as much as possible on hard numbers. That may be a valid explanation, but there is no way to prove that without actually comparing drop rates.