This paper shows the importance of technological synergies among heterogeneous firms for aggregate fluctuations. First, we document six novel empirical facts using microdata that suggest the existence of important technological synergies between trading firms, the presence of positive...

This paper addresses the joint calibration problem of SPX options and VIX options or futures. We show that the problem can be formulated as a semimartingale optimal transport problem under a finite number of discrete constraints, in the spirit of [arXiv:1906.06478]. We introduce a PDE...

Calibrating option pricing models to market prices often leads to optimisation problems to which standard methods (like such based on gradients) cannot be applied. We investigate two models: Heston's stochastic volatility model, and Bates's model which also includes jumps. We discuss how to...

This paper points out an empirical failing of real business cycle models in which unemployment is endogenized through a matching function. One can easily choose a calibration to make the cyclical fluctuation in unemployment as large in the model as it is in the data, or to make the response of...

The Heston model stands out from the class of stochastic volatility (SV) models mainly for two reasons. Firstly, the process for the volatility is nonnegative and mean-reverting, which is what we observe in the markets. Secondly, there exists a fast and easily implemented semi-analytical...