The paper aims at assessing the costs and benefits of antitrust enforcement. The analysis starts with an investigation of why competition is typically worth protecting followed by a collection of empirical evidence which shows that competition actually needs protection by antitrust policy in...

Determinants of a firm's export-sales ratio (degree of internationalisation) are frequently discussed in the literature related to individual firms' export activities. Stylised facts show a positive relationship between firm size and firm age on the one hand and the firm's export-sales ratio on...

Within the last three years, Google has acquired YouTube and DoubleClick and has attempted to control part of Yahoo!'s search advertising business. Two of the deals have not raised antitrust concerns by competition authorities. I review these deals with a focus on consumer welfare. Consumers are...

This paper provides an overview of telecommunications regulation in the U.S. and in Europe. For each region the history of telecommunications regulations as well as the current regulatory regime is portrayed. The focus of this overview is on the question of how unbundling regulations in the...

This paper studies the aggregate substitution and expansion effects triggered by changes in input prices, in a context where firms supply a homogenous commodity and compete in quantities à la Cournot. We derive a sufficient condition for the existence of a Cournot equilibrium and show that this...

This paper documents that standard cross-sectional determinants of firm leverage also apply to the capital structure of large banks in the United States and Europe. We find a remarkable consistency in sign, significance and economic magnitude. Like non-financial firms, banks appear to have...

Normalising CES production functions in the calibration of basic dynamic models allows to choose technology parameters in an economically plausible way. When variations in the elasticity of substitution are considered, normalisation is necessary in order to exclude arbitrary effects. As an...

There is extreme heterogeneity of firms regulated under the European Emissions Trading Scheme (EU ETS) in terms of emissions evels and employed technology. We present a model that shows that behavior of firms under quantity regulation can differ strongly, dependent on the characteristics of the...

This paper empirically estimates the effects of a new thin-capitalization rule on the financing behavior of German corporations employing a fixed effects difference-in-difference approach. We compare treatment and control groups separated by a hypothetical application of the new rule in three...

Contractual and regulatory provisions for access affect incentives to invest in an upgraded network and, in particular, a next-generation access network. Investment decisions are made under uncertainty and have to be made over time. This papers provides a framework for taking uncertainty, risk...