We introduce a new analytical approach to price American options. Using an explicit and intuitive proxy for the exercise rule, we derive tractable pricing formulas using a short-maturity asymptotic expansion. Depending on model parameters, this method can accurately price options with...

In this paper we construct arbitrage-free market models of stochastic volatility type for one stock, one bank account and a finite family of European call options with various strikes and maturities. We first introduce local implied volatilities and price level as market observables which...

In this paper we propose analytical approximations for computing implied volatilities when time-to-maturity t is small. The analysis is performed in the framework of a two-factor model with local and stochastic volatility. We describe an algorithm for building the power series approximation of...