IV

A high IV environment makes options expensive to buy but lucrative for sellers willing to accept the risk.高隐含波动率（IV）环境使得期权购买成本昂贵，但对于愿意承担风险的卖方来说却利润丰厚。

IV crush happens when expected volatility drops after a major event, rapidly reducing the value of long options positions.当重大事件过后预期波动率下降时，就会发生 IV 暴跌（IV crush），从而迅速降低做多期权头寸的价值。