Stocks are exposed to the risk of sudden downward jumps. Additionally, a crash in one stock (or index) can increase the risk of crashes in other stocks (or indices). Our paper explicitly takes this contagion risk into account and studies its impact on the portfolio decision of a CRRA investor...

This paper examines whether and how the popularity of portfolio insurance strategies can be justified theoretically. The analysis employs three different return generating processes with and without stochastic volatility and jumps. We find that an investor with constant relative risk aversion...

We study the optimal portfolio choice of international investors when variances and correlations are stochastic. We assume that the returns from the perspective of the domestic investor are driven by a Wishart Affine Stochastic Correlation (WASC) model. We show that this also holds from the...

We analyze the optimal portfolio choice in a multi-asset Wishart-model in which return variances and correlations are stochastic and subject to jump risk. The optimal portfolio is characterized by the positions in stock diffusion risk, variance-covariance diffusion risk, and jump risk. We find...

We propose a Wishart Affine Stochastic Correlation (WASC) model for the joint dynamics of the SDF in an international economy. We derive exchange rate dynamics and a quasi-closed-form solution for currency option pricing. This solution includes Heston's stochastic volatility model as a special...

This paper deals with the problem of quadratic hedging with limited initial capital. We show (i) that the optimal amount of capital for the quadratic hedge of a portfolio of contingent claims is equal to the sum of optimal investments for the individual hedges of its components and (ii) that the...

We analyze optimal asset allocation in continuous time for a collective of tied-together investors. We rely on a specific collective utility function which dates back to Karatzas (1990), by which the fund manager maximizes the weighted average of expected individual utilities for the investors...