Vast empirical evidence points to the existence of a negative correlation, named ”leverage effect”, between shocks to variance and shocks to returns. We provide a nonparametric theory of leverage estimation in the context of a continuous-time stochastic volatility model with jumps in...

The market for ultra short-term (zero days-to-expiry or 0DTE) options has grown exponentially over the last few years. In 2023, daily volume in 0DTEs reached over 45% of overall daily options volume. After briefly describing this exploding new market, we present a novel pricing formula designed...

We provide nonparametric methods for stochastic volatility modeling. Our methods allow for the joint evaluation of return and volatility dynamics with nonlinear drift and diffusion functions, nonlinear leverage effects, and jumps in returns and volatility with possibly state-dependent jump...

Asset prices can be stale. We define price “staleness” as lack of price adjustments yielding zero returns (i.e., zeros). The term “idleness” (resp. “near idleness”) is, instead, used to define staleness when trading activity is absent (resp. close to absent). Using statistical and...

We introduce a novel economic indicator, named excess idle time (EXIT), measuring the extent of sluggishness in observed financial prices. Using a complete limit theory, we provide econometric support for the fact that high-frequency transaction prices are, coherently with liquidity and...