Well, lets examine how each predator is assumed to attack.
From what we know of a raptor it is assumed that it is a pack animal, and that it uses its numbers to attack and bring down larger creatures with its speed and vicious rending claws. But bear in mind that the raptors claws are designed for the animal to grasp their prey and hold it while rending with their rear claws, much like a cat would do in a fight.
Bears are apex predators, and solo hunters/scavengers. They are also more fast and nimble than people expect because of their size. Their overwhelming strength enables them to crush the bones of their prey often disabling them in one swipe or bite.
This being the case, in a one on one faceoff, I would expect it to go down like this:
Raptor circles bear looking for an opening. Upon finding one, Raptor rushes in and attempts to grapple bear in order to begin rending it with its rear claws. Bear meets rush head on, and its weight and strength surprises and overwhelms the raptor turning its own rush back upon itself. The raptor is able to get a few swipes with its massive claw, but once the bear has the raptor in its grasp its essentially over. There wont be any escape.
The only real concern would be if the raptors claws could somehow penetrate the bears thick skin and possibly eviscarate the bear before the bear kills it. I dont see this stopping the bear from killing the raptor for the simple reason it takes a huge strong animal lilke that a long while to die that way, but it could happen.
I'd put it 90-10 in the bears favor.
