You can build systems that preserve sum of probabilities = 1. They’ll still see bias away from the extremes, because of fees and because of time value of money. But you can do a lot better than PredictIt. (One thing that helps on the fees side is to make fees go down for trades near the extremes; I argued for that in detail on Augur here.
You can build systems that preserve sum of probabilities = 1. They’ll still see bias away from the extremes, because of fees and because of time value of money. But you can do a lot better than PredictIt. (One thing that helps on the fees side is to make fees go down for trades near the extremes; I argued for that in detail on Augur here.