Augur tried this and doesn't seem to have gained a lot traction doing so. Any staking schemes that were developed were relatively easily gamed and that led to distrust in the system.
We, like traditional financial exchanges, define the contracts upfront with clear rules on how they will be settled, then follow the letter of the law very strictly when settling a market.
In general, we've found market certainty to be more important that accuracy: ie. having pre-defined rules that everyone can agree on and that are pre-set is more important than those rules being the "correct rules" (not that having correct rules isn't important).
We, like traditional financial exchanges, define the contracts upfront with clear rules on how they will be settled, then follow the letter of the law very strictly when settling a market.
In general, we've found market certainty to be more important that accuracy: ie. having pre-defined rules that everyone can agree on and that are pre-set is more important than those rules being the "correct rules" (not that having correct rules isn't important).