<div> We propose option realized semivariances and signed jumps as new “observable quantities” to summarize the asymmetric information contained in the sign of high-frequency option returns. These measures successfully capture the direction of the discontinuities related to both the underlying asset and risk factor, yielding incremental information not contained in the aggregate option realized measures. Using options data on S&P 500 ETF (SPY) and 15 individual equities, we document that the negative (positive) semivariance and signed jump of out-of-the-money call (put) options play a prominent role in predicting future variance, variance risk-premia, and excess monthly returns. Out-of-sample volatility timing strategies based on these measures generate economically significant gains of up to 206 basis points annually for risk-averse investors. </div>

We document that implied volatility (IV) curves of short-term equity options frequently become concave prior to earnings announcements day (EAD), typically reflecting a bimodal risk-neutral distribution for the underlying stock price. Firms with concave IV curves exhibit significantly higher absolute stock returns on EAD and higher realized volatility after the announcement, rendering concavity an ex-ante signal for event risk. Returns on delta-neutral straddles, delta-neutral strangles, and delta- and vega-neutral calendar straddles are negative and significantly lower in the presence of concave IV curves, showing that investors pay a substantial premium to hedge against the gamma risk arising from this event.