Whose sentiment explains implied volatility change and smile?

This letter examines the relationship between investor sentiment and options-implied volatility (IV) dynamics using a high-quality intraday dataset. By classifying each trade by investor type and moneyness, we find that sentiment affects intraday IV changes and explains IV structures and anomalies. Domestic individuals’ sentiment is highly related to implied volatility changes and has a more significant effect on out-of-the-money options that noisy individual investors heavily trade.