The prediction market is a way to try to assign probabilities to events. Bettors buy YES bets on things they think are likely to happen (relative to the market price) and NO bets on things they think are unlikely to happen (relative to the market price). Market dynamics lead the market price to settle on what is, across the bettors, the best subjective probability of the event. This is useful if you are trying to assign probabilities to one-off future events.
