In this paper, we derive two shrinkage estimators for the global minimum variance portfolio that dominate the traditional estimator with respect to the out-of-sample variance of the portfolio return. The presented results hold for any number of observations d + 2 and number of assets d 4. The...

In this paper we stress-test credit portfolios of 28 German banks based on a Mertontype multi-factor credit risk model. The ad-hoc stress scenario is an economic downturn in the automobile industry that constitutes an exceptional but plausible event suggested by historical data. Rather than on a...

From a banking supervisory perspective, this paper analyses aspects of market risk of an aggregated trading portfolio comprised of the trading books of 11 German banks with a regulatory approved internal market risk model. Based on real, clean profit and loss data and Value-at-Risk estimates of...

"Arbitrage CDOs" have recorded an explosive growth during the years before the outbreak of the financial crisis. In the present paper we discuss potential sources of such arbitrage opportunities, in particular arbitrage gains due to mispricing. For this purpose we examine the risk profiles of...

In order to shed light on the "black box" of institutional equity investing in a systematic manner, I conducted a broadly based questionnaire which received a large response from German mutual fund companies. The survey asked fund managers for their basic views and practices and for insights...

We employ a life-cycle model with income risk to analyze how tax-deferred individual accounts affect households' savings for retirement. We consider voluntary accounts as opposed to mandatory accounts with minimum contribution rates. We contrast add-on accounts with carve-out accounts that...

We show that including distribution costs into a general equilibrium model of international portfolio choice contributes to explaining the “home bias” in international equity investment. Our model is able to replicate observed investment positions for a wide range of parameter values, even...

Lending specialization on certain industry sectors can have opposing effects on monitoring (including screening) abilities and on the sectoral concentration risk of a credit portfolio. In this paper, we examine in the first part if monitoring abilities of German cooperative banks and savings...

This paper presents a procedure to determine policy feedback rules in dynamic stochastic general equilibrium (DSGE) models. We illustrate our approach with fiscal feedback rules for tax instruments in a standard medium-scale DSGE model. First, we approximate the optimal dynamic behavior of the...