This paper studies modelling and existence issues for market models of option prices in a continuous-time framework with one stock, one bond and a family of European call options for one fixed maturity and all strikes. After arguing that (classical) implied volatilities are ill-suited for...

This paper studies modelling and existence issues for market models of stochastic implied volatility in a continuous-time framework with one stock, one bank account and a family of European options for all maturities with a fixed payoff function h. We first characterize absence of arbitrage in...

Empirically, we show that the proportion of stocks exhibiting conditional heteroscedastic residuals, is high. We suggested to use the market model with GARCH(1,1) residuals in order to describe daily stock returns and derived a test statistics for the null hypothesis of no abnormal returns,...

Information spielt nicht erst seit der digitalen Revolution im Wirtschaftsleben eine herausragende Rolle. Sei es als Information über Güter, etwa über deren Qualität oder Preis, oder als eigenständiges Wirtschaftsgut, z.B. in Form von Nachrichten oder Forschungsergebnissen. Aus einer...

We analyse a two period model of the interbank market, i.e. the market at which banks trade liquidity. We assume that banks do not take the interbank interest rate as given, but multilaterally negotiate on interest rates and transaction volumes. The solution concept applied is the Shapley value....

The rational expectations equilibrium has been criticized as an equilibrium concept in market game environments. Such an equilibrium may not exist generically, or it may introduce unrealistic assumptions about an economic agent's knowledge or computational ability. We define a rational...