Citation
Discussion Paper Details
Please find the details for DP5652 in an easy to copy and paste format below:
Full Details | Bibliographic Reference
Full Details
Title: Selecting Copulas for Risk Management
Author(s): Kees Koedijk, Erik Kole and Marno Verbeek
Publication Date: April 2006
Keyword(s): copulas, distributional tests, financial dependence, risk management and tail dependence
Programme Area(s): Financial Economics
Abstract: Copulas offer financial risk managers a powerful tool to model the dependence between the different elements of a portfolio and are preferable to the traditional, correlation-based approach. In this paper we show the importance of selecting an accurate copula for risk management. We extend standard goodness-of-fit tests to copulas. Contrary to existing, indirect tests, these tests can be applied to any copula of any dimension and are based on a direct comparison of a given copula with observed data. For a portfolio consisting of stocks, bonds and real estate, these tests provide clear evidence in favour of the Student?s t copula, and reject both the correlation-based Gaussian copula and the extreme value-based Gumbel copula. In comparison with the Student?s t copula, we find that the Gaussian copula underestimates the probability of joint extreme downward movements, while the Gumbel copula overestimates this risk. Similarly we establish that the Gaussian copula is too optimistic on diversification benefits, while the Gumbel copula is too pessimistic. Moreover, these differences are significant.
For full details and related downloads, please visit: https://cepr.org/active/publications/discussion_papers/dp.php?dpno=5652
Bibliographic Reference
Koedijk, K, Kole, E and Verbeek, M. 2006. 'Selecting Copulas for Risk Management'. London, Centre for Economic Policy Research. https://cepr.org/active/publications/discussion_papers/dp.php?dpno=5652