Ivan Luciano Danesi, Fabio Piacenza, E. Ruli, L. Ventura
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引用次数: 6
Abstract
One of the aims of operational risk modelling is to generate sound and reliable quantifications of the risk exposure, including a level of volatility that is consistent with the changes of the risk profile. One way for assuring this is by means of robust procedures, such as Optimal B-Robust estimating equations. In banking practice more than one dataset should be incorporated in the risk modelling and a coherent way to proceed to such a data integration is via Bayesian procedures. However, Bayesian inference via estimating equations in general is problematic since the likelihood function is not available. We illustrate that this issue can be dealt with using approximate Bayesian computation methods with the robust estimating function as a summary of the data. The method is illustrated by a real dataset.
期刊介绍:
In December 2017, the Basel Committee published the final version of its standardized measurement approach (SMA) methodology, which will replace the approaches set out in Basel II (ie, the simpler standardized approaches and advanced measurement approach (AMA) that allowed use of internal models) from January 1, 2022. Independently of the Basel III rules, in order to manage and mitigate risks, they still need to be measurable by anyone. The operational risk industry needs to keep that in mind. While the purpose of the now defunct AMA was to find out the level of regulatory capital to protect a firm against operational risks, we still can – and should – use models to estimate operational risk economic capital. Without these, the task of managing and mitigating capital would be incredibly difficult. These internal models are now unshackled from regulatory requirements and can be optimized for managing the daily risks to which financial institutions are exposed. In addition, operational risk models can and should be used for stress tests and Comprehensive Capital Analysis and Review (CCAR). The Journal of Operational Risk also welcomes papers on nonfinancial risks as well as topics including, but not limited to, the following. The modeling and management of operational risk. Recent advances in techniques used to model operational risk, eg, copulas, correlation, aggregate loss distributions, Bayesian methods and extreme value theory. The pricing and hedging of operational risk and/or any risk transfer techniques. Data modeling external loss data, business control factors and scenario analysis. Models used to aggregate different types of data. Causal models that link key risk indicators and macroeconomic factors to operational losses. Regulatory issues, such as Basel II or any other local regulatory issue. Enterprise risk management. Cyber risk. Big data.