Online Consumer-to-Consumer Communication Networks are characterized by informational and social benefits as well as time and effort costs for participants. Therefore, this dissertation takes an economic perspective on the network formation process as a determinant of value for consumers and...

Using a model selection approach, this thesis proposes a constructive data-and-theory-combined procedure to identify model structures in the framework of a linear simultaneous equations system based on observed data. A model structure is characterized by restrictions on the structural...

In an increasingly competitive environment, firms have to optimally adjust both their allocation of input factors and their technology portfolio. The latter determines economies of scope and scale in future research and production. The aim of this dissertation is to achieve better insight into...

This dissertation consists of three stand-alone research papers, all of which treat the topic of estimation and dynamic modelling of multivariate volatility by employing the information contained in high-frequency data, which became available in the last 10 - 15 years. The main focus of all...

This dissertation introduces three novel approaches for the econometric evaluation of heterogeneous treatment effects. The proposed methods consider the effects of a binary treatment on different characteristics of the outcome distribution.Section 1 proposes an estimation method for various...

In recent years high-frequency finance has become one of the most active research fields in finance and economics. The wide-spread availability of high-frequency datasets has particularly spurred research within this field and has, in turn, given birth to the rapidly expanding bridge between...

This dissertation is comprised of three essays on nonparametric Bayesian modeling in microeconometrics. The introduction discusses some basic concepts of Bayesian nonparametrics including the Dirichlet process and the mixture of Dirichlet processes model. Further, the literature on estimating...

The development of a feasible and flexible model for the intraday transaction process is an ongoing topic in the empirical analysis of market microstructure. This work attempts to modify and extend the models of the transaction process suggested by Rydberg and Shephard (1998) and Russell and...

Das deutsche Hochschulsystem befindet sich zur Zeit in einerstarken Umstrukturierungsphase. Dabei ist neben der Einführung derMaster- und Bachelorstudiengängen die Einführung vonStudiengebühren eine der einschneidendsten Politikmaßnahmen, diein Deutschland im tertiären Bildungsbereich...