Efficient Control Variates and Strategies for Bermudan Swaptions in a Libor Market Model

Abstract

This paper concerns the problem of valuing Bermudan swaptions in a Libor market model. In particular we consider various efficiency improvement techniques for a Monte Carlo based valuation method. We suggest a simplification of the Andersen (2000) exercise strategy and find it to be much more efficient. Furthermore, we test a range of control variates for Bermudan swaptions using a control variate technique for American options proposed in Rasmussen (2002). Application of these efficiency improvements in the Primal-Dual simulation algorithm of Andersen & Broadie (2001) improves both upper and lower bounds for the price estimates. For the Primal-Dual simulation algorithm we examine the variance-bias trade-off between the numbers of outer an inner paths. Finally, we demonstrate that the presence of stochastic volatility increases the expected losses from using the simple strategy in Andersen (2000).Bermudan Swaptions; Control Variates; Exercise Strategy; Primal-Dual Algorithm; Stochastic Volatility