Results from portfolio models for credit risk tell us that loan concentration in certain industry sectors can substantially increase the value-at-risk (VaR). The purpose of this paper is to analyze whether a tractable "infection model" can provide a meaningful estimate of the impact of...

Since the early 1990s an unprecedented process of consolidation has taken place in the banking sector in most industrialised countries raising concern of policymakers that it may reduce access to credit for the small business sector. While most of the existing empirical studies have focused on...

Die öffentliche Diskussion über die Struktur des Lebensmitteleinzelhandels in Deutschland ist durch die Sorge über ein hohes Niveau (bzw. die weitere Zunahme) der Konzentration auf Unternehmensebene sowie eine Abnahme der Zahl der Verkaufsstätten geprägt. Die vorliegende Arbeit sucht nach...

Substantial increases in retail concentration (particularly in Europe) raise concerns about the welfare implications for consumers. In a formal model, we argue that retailer market power reduces upstream firms incentives to introduce new products. On the basis of a survey of firms in German food...

The last couple of decades have seen an increased retail concentration around the world, particularly in Europe. Views on the welfare implications of this severe change are controversial. Consumers might benefit because larger stores (owned by larger retailer chains) offer more product choices....

Theory predicts a positive relationship between market concentration and profitability in most scenarios. In empirical work, however, this relation is frequently not found or only a weak connection is observed. We compare the performance of concentration and market share variables, which are...