We consider the standard discrete-time model of a frictionless financial market and show that the law of one price holds if and only if there exists a martingale density process with strictly positive initial value. In contrast to the classical no-arbitrage criteria, this density process may...

We investigate the term structure of zero coupon bonds when interest rates are driven by a general marked point process as well as by a Wiener process. Developing a theory that allows for measure-valued trading portfolios, we study existence and uniqueness of a martingale measure. We also study...

Inspired by the theory of financial markets with transaction costs, we study a concept of essential supremum in the framework where a random partial order in View the MathML source is lifted to the space View the MathML source of d-dimensional random variables. In contrast to the classical...