In this paper, we show that coherent upper and lower previsions as well as coherent risk measures are only meaningful under the assumption that one starts with initial wealth being constantly 0. This implies at least for coherent upper and lower previsions a correction of their interpretation,...

A class of contribution values for pairs of random variables is introduced as a technical tool for the problem how the risk capital needed for a portfolio of random activities should be allocated to its components. The well known allocation model with expected shortfall as corresponding risk...

In June 2003 Swiss banks held over CHF 500 billion in mortgages. This important segment accounts for about 63% of all loan portfolios of Swiss banks. Since default insurance is not common in Switzerland, the corresponding risks are a severe threat for the health of the financial system. We...

We introduce an adaptive importance sampling method for the loss distribution of credit portfolios based on the Robbins-Monro stochastic approximation procedure. After presenting the subtle construction of the algorithm, we apply our adaptive scheme for calculating the risk figures of a typical...

We derive a general framework for collateral risk control determination for central bank's open market operations. This framework allows us to determine the schedule of haircuts consistent with the risk tolerated by the central bank while at the same time reducing the possibility of arbitrage...

We investigate the influence of various variables on credit default swap transaction data. Credit derivatives are arguably a superior proxy to credit risk than bond spreads. The variables considered include fixed-income as well as equity markets data. We thus provide an international analysis of...

This paper presents a utility-based approach to value the borrower optimal behavior in presence of credit risk. The paper solves for the dynamic portfolio choices of a borrower. We thereby show that the presence of debt leads to a substantial modification in the borrower's behavior across states...

Natural catastrophes attract regularly the attention of media and have become a source of public concern. From a financial viewpoint, natural catastrophes represent idiosyncratic risks,diversifiable at the world level. But for reasons analyzed in this pap er reinsurance markets are unable to...

In this paper we discuss some statistical pitfalls that may occur in modeling cross-dependences with copulas in financial applications. In particular we focus on issues arising in the estimation and the empirical choice of copulas as well as in the design of time-dependent copulas.

This paper argues that observations of non-stationary choice behavior need notnecessarily imply specific properties of the individual’s discount function. As weshow, the observed “anomalies” in intertemporal choice can alternatively be explained by an individual’s perception of the risk...