Measuring portfolio credit risk correctly: why parameter uncertainty matters
Why should risk management systems account for parameter uncertainty? In order to answer this question, this paper lets an investor in a credit portfolio face non-diversifiable estimation-driven uncertainty about two parameters: probability of default and asset-return correlation. Bayesian inference reveals that - for realistic assumptions about the portfolio's credit quality and the data underlying parameter estimates - this uncertainty substantially increases the tail risk perceived by the investor. Since incorporating parameter uncertainty in a measure of tail risk is computationally demanding, the paper also derives and analyzes a closed-form approximation to such a measure.
|Date of creation:||Apr 2009|
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- Bongaerts, Dion & Charlier, Erwin, 2009. "Private equity and regulatory capital," Journal of Banking & Finance, Elsevier, vol. 33(7), pages 1211-1220, July.
- Forte, Santiago & Peña, Juan Ignacio, 2009. "Credit spreads: An empirical analysis on the informational content of stocks, bonds, and CDS," Journal of Banking & Finance, Elsevier, vol. 33(11), pages 2013-2025, November.
- Merton, Robert C., 1973.
"On the pricing of corporate debt: the risk structure of interest rates,"
684-73., Massachusetts Institute of Technology (MIT), Sloan School of Management.
- Merton, Robert C, 1974. "On the Pricing of Corporate Debt: The Risk Structure of Interest Rates," Journal of Finance, American Finance Association, vol. 29(2), pages 449-70, May.
- Michael B. Gordy, 2002.
"A risk-factor model foundation for ratings-based bank capital rules,"
Finance and Economics Discussion Series
2002-55, Board of Governors of the Federal Reserve System (U.S.).
- Gordy, Michael B., 2003. "A risk-factor model foundation for ratings-based bank capital rules," Journal of Financial Intermediation, Elsevier, vol. 12(3), pages 199-232, July.
- Lando, David & Skodeberg, Torben M., 2002. "Analyzing rating transitions and rating drift with continuous observations," Journal of Banking & Finance, Elsevier, vol. 26(2-3), pages 423-444, March.
- Borio, Claudio & Tsatsaronis, Kostas, 2004. "Accounting and prudential regulation: from uncomfortable bedfellows to perfect partners?," Journal of Financial Stability, Elsevier, vol. 1(1), pages 111-135, September.
- Zhu, Haibin & Tarashev, Nikola A., 2008. "The pricing of correlated default risk: evidence from the credit derivatives market," Discussion Paper Series 2: Banking and Financial Studies 2008,09, Deutsche Bundesbank, Research Centre.
- Lütkebohmert, Eva & Gordy, Michael B., 2007. "Granularity adjustment for Basel II," Discussion Paper Series 2: Banking and Financial Studies 2007,01, Deutsche Bundesbank, Research Centre.
- Liao, Hsien-Hsing & Chen, Tsung-Kang & Lu, Chia-Wu, 2009. "Bank credit risk and structural credit models: Agency and information asymmetry perspectives," Journal of Banking & Finance, Elsevier, vol. 33(8), pages 1520-1530, August.
- Kerkhof, Jeroen & Melenberg, Bertrand & Schumacher, Hans, 2010. "Model risk and capital reserves," Journal of Banking & Finance, Elsevier, vol. 34(1), pages 267-279, January.
- Nikola Tarashev & Haibin Zhu, 2008. "Specification and Calibration Errors in Measures of Portfolio Credit Risk: The Case of the ASRF Model," International Journal of Central Banking, International Journal of Central Banking, vol. 4(2), pages 129-173, June.
- Hanson, Samuel & Schuermann, Til, 2006. "Confidence intervals for probabilities of default," Journal of Banking & Finance, Elsevier, vol. 30(8), pages 2281-2301, August.
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