Dieses Paper widmet sich der Übertragbarkeit des Spillover-Effektes auf die Suchmaschinen-Werbung, insbesondere wird eine Wirkungsübertragung von der generischen Suche auf die Suche mit Marken-Keywords analyisiert und interpretiert. Diese Wirkungsübertragung findet annahmegemäß dadurch...

In this paper we give an overview, with special emphasis on Germany, of the recent development of the market for venture capital. We analyse the financial contracting problems that arise when entrepreneurs need capital from outside investors, and demonstrate how these problems are addressed by...

To investigate the external validity of laboratory results, we combine a public good experiment with three treatments in a field experiment. One treatment offers the opportunity to free-ride, the other two are placebo treatments. We compare results within subjects. In the free-riding treatment,...

We run a public good experiment in the field and in the lab with (partly) the same subjects. The field experiment is a true natural field experiment as subjects do not know that they are exposed to an experimental variation. We can show that subjects' behavior in the classic lab public good...

Does the internet increase competition? To address this question, I exploit two institutional details unique to Germany: (1) Some municipalities received glass fibre cables that cannot be upgraded to DSL; I use these municipalities as a treatment group with reduced online competition. (2) German...

We study an exchange economy in which investors are loss averse over relative consumption, that is, they suffer a utility loss if they consume less than members of their reference group. As a consequence there is an incentive to hold the same portfolio of risky assets as the reference group....

When a young entrepreneurial firm matures, it is often necessary to replace the founding entrepreneur by a professional manager. This replacement decision can be affected by the private benefits of control enjoyed by the entrepreneur which gives rise to a conflict of interest between the...

This paper develops a theory why innovation often takes place in new firms that depend overproportionally on external finance usually supplied by specialist intermediaries called venture capitalists. It is argued that innovative projects are characterized by two features: uncertainty that is...