Value at Risk (VaR) has emerged in recent years as a standard tool to measure and control the risk of trading portfolios. Yet, existing theoretical analyses of the optimal behavior of a trader subject to VaR limits have produced a negative view of VaR as a risk-control tool. In particular, VaR...

We analyze a portfolio optimization problem for a long-term investor in the presence of stock market crises. A crisis includes a crash of the stock market price, a sharp increase of its volatility and dramatic deterioration of liquidity. We model the stock market illiquidity by means of convex...