Sometimes you don't need to make a study showing some number to act on something.
It can be a simple chain of logic saying: % of children try to test their boundaries. Of those children some get away with it, some don't. Of those who get away with it, they carry on doing it, and it has reprecussions down the line. If you look at the problem this way, it's a rational take on caning - to tighten the net against bullying.
Posted more context here: