Abstract
Risk aggregation considering inter-risk dependence has always been a challenge to both researchers and practitioners. The objective of this study is to formulate ways of aggregation of bank risks and comprehensively compare simple summation, variance–covariance and copula approach. Firstly, the three popular approaches are adopted to aggregate credit risk, market risk and operational risk of banks based on Austrian banking data. Then, two comparisons are mainly made. Total risks aggregated by different approaches are compared to analyze their relative magnitudes. Diversification benefits of different approaches are further compared to investigate their tail dependence structures. Based on the empirical analysis, some facts are verified and some interesting findings are uncovered, leading to the conclusions that simple summation approach is too conservative and variance–covariance approach is overly optimistic, so it is suggested that copula approach is the future major trend for bank risk aggregation. Especially, t copula with degree of freedom between 1 and 10 is a good choice to capture tail dependence while Gaussian copula is not recommended. Besides, the proposed mixture copula consisting of t copula and Gumbel copula exhibits heavier right tail dependence than single t copula.
Similar content being viewed by others
References
Aas K, Dimakos XK, Oksendal A (2007) Risk capital aggregation. Risk Manag 9(2):82–107
Alessandri P, Drehmann M (2010) An economic capital model integrating credit and interest rate risk in the banking book. J Bank Financ 34:752–764
Alexander C, Pezier J (2003) On the aggregation of market and credit risks. ISMA centre discussion papers in finance no. 2003–2013, University of Reading
Antao P, Lacerda A (2011) Capital requirements under the credit risk-based framework. J Bank Financ 35:1380–1390
Basel Committee on Banking Supervision (1988) International convergence of capital measurement and capital standards. Bank for International Settlements, Basel
Basel Committee on Banking Supervision (1995) An internal model-based approach to market risk capital requirements. Bank for International Settlements, Basel
Basel Committee on Banking Supervision (1996) Amendment to the capital accord to incorporate market risks. Bank for International Settlements, Basel
Basel Committee on Banking Supervision (2001) Working paper on the regulatory treatment of operational risk. Bank for International Settlements, Basel
Basel Committee on Banking Supervision (2003) Trends in risk integration and aggregation. Bank for International Settlements, Basel
Basel Committee on Banking Supervision (2004) International convergence of capital measurement and capital standards: a revised framework. Bank for International Settlements, Basel
Basel Committee on Banking Supervision (2011) Messages from the academic literature on risk measurement for the trading book. Bank for International Settlements, Basel
Böcker K, Hillebrand M (2009) Interaction of market and credit risk: an analysis of inter-risk correlation and risk aggregation. J Risk 11(4):3–29
Breuer T, Jandacka M, Rheinberger K, Summer M (2010) Does adding up of economic capital for market and credit risk amount to conservative risk assessment? J Bank Financ 34:703–712
Brockmann M, Kalkbrener M (2010) On the aggregation of risk. J Risk 12(3):45–68
Chen YH, Tu AH (2013) Estimating hedged portfolio value-at-risk using the conditional copula: an illustration of model risk. Int Rev Econ Financ 27:514–528
Cherubini U, Luciano E, Vecchiato W (2004) Copula methods in finance. Wiley, UK
Cruz M, Coleman R, Salkin G (1998) Modeling and measuring operational risk. J Risk 1:63–72
De Fontnouvelle P, Jesus-Rueff V, Jordan J, Rosengren E (2006) Capital and risk: new evidence on implications of large operational losses. J Money Credit Bank 38:1819–1846
Demarta S, McNeil AJ (2005) The t copula and related copulas. Int Stat Rev 73:111–130
Dimakos XK, Aas K (2004) Integrated risk modeling. Stat Model 4:265–277
Drehmann M, Sorensen S, Stringa M (2010) The integrated impact of credit and interest rate risk on banks: a dynamic framework and stress testing application. J Bank Financ 34:735–751
Elsinger H, Lehar A (2006) Risk assessment for banking systems. Manag Sci 52:1301–1314
Embrechts P, McNeil AJ, Straumann D (1999) Correlation: pitfalls and alternatives. Risk 12:69–71
Embrechts P, Furrer H, Kaufmann R (2003) Quantifying regulatory capital for operational risk. J Deriv Hedge Funds 9:217–233
Feng J, Chen J, Li J (2010) Operational risk measurement via the loss distribution approach. In: Liu S, Forrest J (eds) Advances in grey systems research: understanding complex systems. Springer Berlin Heidelberg, p 493–502
Forum Joint (2001) Risk management practices and regulatory capital, cross sectoral comparison. Bank for International Settlements, Basel
Forum Joint (2010) Developments in modelling risk aggregation. Bank for International Settlements, Basel
Francis WB, Osborne M (2012) Capital requirements and bank behavior in the UK: are there lessons for international capital standards? J Bank Financ 36:803–816
Gao L, Li J, Xu W (2006) Assessment the operational risk for Chinese commercial banks. Lect Notes Comput Sci 3994:501–508
Glasserman P, Heidelberger P, Shahabuddin P (2002) Portfolio value-at-risk with heavy-tailed risk factors. Math Financ 12:239–270
Grundke P (2010) Top-down approaches for integrated risk management: how accurate are they? Eur J Oper Res 203:662–672
Hu L (2006) Dependence patterns across financial markets: a mixed copula approach. Appl Financ Econ 16:717–729
Huang M, Wu C (2013) Economic benefits and determinants of extreme dependences between REIT and stock returns. Rev Quant Financ Acc. doi:10.1007/s11156-013-0407-3
Hull J (2012) Risk management and financial institutions, 3rd edn. John Wiley & Sons, Hoboken, USA
Inanoglu H, Jacobs M (2009) Models for risk aggregation and sensitivity analysis: an application to bank economic capital. J Risk Financ Manag 2:118–189
International Financial Risk Institute Foundation and Chief Risk Officer Forum (2007) Insights from the joint IFRI/CRO Forum survey on economic capital practice and applications. KPMG Business Advisory Services
Jarrow RA, Turnbull SM (2000) The intersection of market and credit risk. J Bank Financ 24(1–2):271–299
Jorion P (2007) Value at risk: the new benchmark for managing financial risk, 3rd edn. McGraw-Hill, New York
Kole E, Koedijk K, Verbeek M (2007) Selecting copulas for risk management. J Bank Financ 31:2405–2423
Kretzschmar G, McNeil A, Kirchner A (2010) Integrated models of capital adequacy—why banks are undercapitalized. J Bank Financ 34:2838–2850
Kuritzkes A, Schuermann T (2007) What we know, don’t know and can’t know about bank risk: a view from the trenches. The known the unknown and the unknowable in financial risk management. Princeton University Press, Princeton
Kuritzkes A, Schuermann T, Weiner SM (2001) Study on the risk profile and capital adequacy of financial conglomerates. A study commissioned by the supervisory bodies in the Netherlands together with the representative organizations of the financial sector. Oliver Wyman, New York
Kuritzkes A, Schuermann T, Weiner SM (2003) Risk measurement, risk management, and capital adequacy in financial conglomerates. Brookings-Wharton papers on financial services. Brookings Institution Press, Washington
Li J, Feng J, Chen J (2009) A piecewise-defined severity distribution based loss distribution approach to estimate operational risk: evidence from Chinese national commercial banks. Int J Inf Technol Decis Mak 8:727–747
Li J, Feng J, Sun X, Li M (2012) Risk integration mechanisms and approaches in banking industry. Int J Inf Technol Decis Mak 11(6):1183–1213
Lin W (2000) The role of the financial early-warning system in strengthening financial supervision and the deposit insurance mechanism. Rev Pac Basin Financ Mark Policies 3(2):269–308
Matthias M, Grisar C, Kuhnert F (2011) The impact of biases on simulation-based risk aggregation: modeling cognitive influences on risk assessment. J Manag Control 22:79–105
Mitschele A, Schlottmann F, Seese D (2008) Integrated risk management: risk aggregation and allocation using intelligent systems. In: Kontoghiorghes E, Rustem B, Winker P (eds) Computational methods in financial engineering. Springer Berlin Heidelberg, p 317–342
Morone M, Cornaglia A, Mignola G (2007) Economic capital assessment via copulas: aggregation and allocation of different risk types. Working paper
Nelson RB (1999) An introduction to copulas. Springer, New York
Perignon C, Smith DR (2010) Diversification and value-at-risk. J Bank Financ 34(1):55–66
Rachev ST, Menn C, Fabozzi F (2005) Fat-tailed and skewed asset return distributions: implications for risk management, portfolio selection, and option pricing. Wiley, New York
Rodriguez JC (2007) Measuring financial contagion: a copula approach. J Empir Financ 14:401–423
Rosenberg JV, Schuermann T (2006) A general approach to integrated risk management with skewed, fat-tailed risks. J Financ Econ 79(3):569–614
Schlottmann F, Mitschele A, Seese D (2005) A multi-objective approach to integrated risk management. Evol Multi-Criterion Optim 3410:692–706
Skoglund J (2010) Risk aggregation and economic capital. SAS Institute Incorporated Company, Cary
Tang A, Valdez EA (2006) Economic capital and the aggregation of risks using Copulas. http://papers.ica2006.com/1A.html
Ward L, Lee D (2002) Practical application of risk-adjusted return on capital framework. CAS Forum Summer, Dynamic financial analysis discussion paper
Weiß GNF (2013) Copula-GARCH versus dynamic conditional correlation: an empirical study on VaR and ES forecasting accuracy. Rev Quant Financ Acc 41:179–202
Acknowledgments
This research has been supported by Grants from the National Natural Science Foundation of China (71071148, 70701033), Key Research Program of Institute of Policy and Management, Chinese Academy of Sciences (Y201171Z05) and Youth Innovation Promotion Association of the Chinese Academy of Sciences. The author also would like to thank the anonymous reviewers for their very valuable and professional suggestions.
Author information
Authors and Affiliations
Corresponding author
Electronic supplementary material
Below is the link to the electronic supplementary material.
Rights and permissions
About this article
Cite this article
Li, J., Zhu, X., Lee, CF. et al. On the aggregation of credit, market and operational risks. Rev Quant Finan Acc 44, 161–189 (2015). https://doi.org/10.1007/s11156-013-0426-0
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11156-013-0426-0