In this paper, we use detailed data on the sovereign debt holdings of all German banks to analyse the determinants of sovereign debt exposures and the implications of sovereign exposures for bank risk. Our main findings are as follows. First, sovereign bond holdings are heterogeneous across...

We develop a macroeconomic portfolio stress test that is specifically geared towards small and medium-sized banks. We combine a credit risk stress test which simulates credit impairments via a CreditMetrics type multi-factor portfolio model with an income stress test in the form of dynamic panel...

Using a unique data set on German banks' sector specific loan exposures to the real economy and the corresponding write-offs and write-downs, we examine the impact of loan portfolio sector concentration on credit risk. By controlling for common risk factors, we separate the bank-specific...

This paper deals with stress tests for credit risk and shows how exploiting the discretion when setting up and implementing a model can drive the results of a quantitative stress test for default probabilities. For this purpose, we employ several variations of a CreditPortfolioView-style model...

We show that banks' risk exposure in one asset category affects how they report regulatory risk weights for another asset category. Specifically, banks report lower credit risk weights for their loan portfolio when they face higher risk exposure in their trading book. This relationship is...

We introduce a novel simulation-based network approach, which provides full-edged distributions of potential interbank losses. Based on those distributions we propose measures for (i) systemic importance of single banks, (ii) vulnerability of single banks, and (iii) vulnerability of the whole...

The internal ratings-based (IRB) approach maps bank risk profiles more adequately than the standardized approach. After switching to IRB, banks' risk-weighted asset (RWA) densities are thus expected to diverge, especially across countries with different supervisory strictness and risk levels....

This paper provides evidence for regulatory arbitrage within the class of assetbacked securities (ABS) based on individual asset holding data of German banks. I find that those banks operating with tight regulatory constraints pick the securities with the highest yield and lowest collateral...

We propose an algorithm to model contagion in the interbank market via what we term the credit quality channel. In existing models on contagion via interbank credit, external shocks to banks often spread to other banks only in case of a default. In contrast, shocks are transmitted via asset...

Regulatory capital for trading book positions includes two components that cover different risks but apply to the same portfolio, one for market risk and one for credit risk. Similar approaches are common in banks’ internal models for economic capital. Although it is known that joint market...