Using the next-day and next-week returns of stocks in the Korean market, we examine the association of option volume ratios - i.e. the option-to-stock (O/S) ratio, which is the total volume of put options and call options scaled by total underlying equity volume, and the put-call (P/C) ratio,...

We examine how informed traders trade in the option market around news announcements. We show that their profits depend on whether positions are long or short, whether trades take place before or after news releases, and whether events are scheduled or unscheduled. We predict and find that...

We document that a theoretically founded, real-time, and easy-to-implement option-based measure, termed synthetic-stock difference (SSD), accurately estimates the part of stock's expected return arising from stock's transaction costs. We calculate SSD for U.S. optionable stocks. SSD can be more...