Consistent price systems and face-lifting pricing under transaction costs
arXiv:0803.4416 · doi:10.1214/07-AAP461
Abstract
In markets with transaction costs, consistent price systems play the same role as martingale measures in frictionless markets. We prove that if a continuous price process has conditional full support, then it admits consistent price systems for arbitrarily small transaction costs. This result applies to a large class of Markovian and non-Markovian models, including geometric fractional Brownian motion. Using the constructed price systems, we show, under very general assumptions, the following ``face-lifting'' result: the asymptotic superreplication price of a European contingent claim equals , where is the concave envelope of and is the price of the asset at time . This theorem generalizes similar results obtained for diffusion processes to processes with conditional full support.
Published in at http://dx.doi.org/10.1214/07-AAP461 the Annals of Applied Probability (http://www.imstat.org/aap/) by the Institute of Mathematical Statistics (http://www.imstat.org)