We solve the problem of mean-variance hedging for general semimartingale models via stochastic control methods. After proving that the value process of the associated stochastic control problem has a quadratic structure, we characterise its three coefficient processes as solutions of...

We propose a simplified approach to mean-variance portfolio problems by changingtheir parametrisation from trading strategies to final positions. This allows us to treat,under a very mild no-arbitrage-type assumption, a whole range of quadratic optimisationproblems by simple mathematical tools...

The Markowitz problem consists of finding in a financial market a self-financingtrading strategy whose final wealth has maximal mean and minimal variance. Westudy this in continuous time in a general semimartingale model and under coneconstraints: Trading strategies must take values in a...

We study mean-variance hedging under portfolio constraints in a general semi-martingale model. The constraints are formulated via predictable correspondences,meaning that the trading strategy is restricted to lie in a closed convex set whichmay depend on the state and time in a predictable way....

The purpose of this paper is two-fold. First is to extend the notions of an n-dimensional semimartingaleand its stochastic integral to a piecewise semimartingale of stochastic dimension. The propertiesof the former carry over largely intact to the latter, avoiding some of the pitfalls of...

Following a trend of sustained and accelerated growth, the VIXfutures and options market has become a closely followed, active andliquid market. The standard stochastic volatility models | whichfocus on the modeling of instantaneous variance | are unable to t theentire term structure of VIX...

For an investor with constant absolute risk aversion and a long horizon, who trades in amarket with constant investment opportunities and small proportional transaction costs, weobtain explicitly the optimal investment policy, its implied welfare, liquidity premium, andtrading volume. We...

In a market with one safe and one risky asset, an investor with a long horizon, constantinvestment opportunities, and constant relative risk aversion trades with small proportionaltransaction costs. We derive explicit formulas for the optimal investment policy, its impliedwelfare, liquidity...

We develop an econometric methodology to infer the path of risk premia from large unbalancedpanel of individual stock returns. We estimate the time-varying risk premia implied by conditional linearasset pricing models where the conditioning includes instruments common to all assets and asset...