This paper summarizes the peculiarities of online markets and discusses recent antitrust cases related to online markets. Following a brief description of the online markets' characteristics and potential tendencies for concentration the paper first discusses the antitrust allegations and...

Given various recent antitrust investigations on the retail sector, we deal with uncovering demand systems substitution patterns for a particular market (diapers) to investigate the inter-format competition (supermarkets vs. discounters vs. drugstores). Using the uncovered demand system we...

This paper estimates demand elasticities for the Turkish mobile telecommunication market. In contrast to most other studies, firm level data is used to estimate dynamic panel data models including instrumental variable techniques. Both short- and long-run elasticities are calculated, yielding a...

We analyze how network regulation affects investment into network infrastructure and complementary services. While regulation negatively affcets investment incentives in the regulated network market, the effects of network regulation on investment in complementary services can be either negative...

This paper analyses the extent of inter-format retail competition between supermarkets, discounters and drugstores in Germany, using data from the German market for diapers. We estimate a random coefficient logit model at the individual household level. Based on consumer substitution patterns,...

This paper examines the consequences of introducing mobile number portability (MNP). As MNP allows consumers to keep their telephone number when switching providers, it reduces consumers’ switching costs. However, MNP may also cause consumer ignorance if telephone numbers no longer identify...

We examine how different pass-through rates, from input- to final consumer prices, and different vertical contracts affect upstream market definition. Our theory model predicts that, under reasonable conditions, higher pass-through rates lead to definitions of larger upstream markets. Data...