We present a geometric approach to discrete time multiperiod mean variance portfolio optimization that largely simplifies the mathematical analysis and the economic interpretation of such model settings. We show that multiperiod mean variance optimal policies can be decomposed in an orthogonal...

We propose a new continuous time framework to study asset prices under learning and ambiguity aversion. In a partial information Lucas economy with time additive power utility, a discount for ambiguity arises if and only if the elasticity of intertemporal substitution (EIS) is above one. Then,...

In a Lucas exchange economy with standard power utility, we study asset prices under learning and ambiguous information. In contrast with models featuring only learning or ambiguity, our model is successful in matching the equity premium, the interest rate, and the volatility of stock returns...

We examine the quantification of operational risk for banks. We adopt a financial-economics approach and interpret operational risk management as a means of optimizing the profitability of an institution along its value chain. We start by defining operational risk and then propose a...

We propose a simple and implementable model of credit contagion where we in-clude macro- and microstructural dependencies among the debtors within a creditportfolio. We show that, even for diversified portfolios, moderate microstructuraldependencies have already a significant impact on the tails...

In this paper operational risk are considered from a purely business or profitability point of view. We show for quantifiable operational risk that the three basic figures for profitability management - value, costs and risks - can be modelled such that an integrative point of view on...

Credit limit management is of paramount importance for successful short-term credit-risk management, even more so when the situation in credit and financial markets is tense. We consider a continuous-time model where the credit provider and the credit taker interact within a game-theoretic...

The financial industry puts the Basle Committee under strain to align regulatory capital with economic capital. This could be reached by allowing more flexibility in the choice of risk measure for regulatory reporting. Markus Leippold and Paolo Vanini show that if banks could use the...