Regarding #事件合约 , my view is that event contracts are just betting on size.

When the price is high, bet that it will go down, 100u. A one-hour deadline (if it really goes down, otherwise, you could lose 100u). Then, at half an hour, place a bet that it will go up. Also 100u. If the final price falls within the size range, you earn 170u; if it falls outside the size range, you lose a 30u fee. In any case, there will be three possible outcomes: 1. falls within the size range, you earn 170u, 2. falls outside the price range, you lose 30u, 3. you may not be able to hedge at the half-hour mark, but ultimately win, earning 85u, or ultimately lose, losing 100u.