Targeted advertising can benefit consumers through lower prices for access to websites. Yet, if consumers dislike that websites collect their personal information, their welfare may go down. We study competition for consumers between websites that can show targeted advertisements. We find that...

During the last twenty years the share of researchers in the workforce has been rising in OECD countries. The consistency of this pattern suggests that it is not a transitional phenomenon. This paper demonstrates that the rise of research can occur in the steady state when schooling inequality...

Distributed Denial of Service (DDoS) attacks are a frequently occurring type of cybercrime, with potentially large costs to the real economy. We propose a simple model of the size and direction of DDoS attacks. The main predictions of the model are that effective botnets are located in...

This note shows that the antilog of Shannon’s entropy is a suitableindex of product variety for three reasons. First, for symmetricproduct types it is equal to the number of product types. Second, disaggregationof the underlying product set always leads to an increasein measured product...

In this paper, the effects of uncertainty and of various policy instruments on the lengthand attractiveness of private research projects are studied. Research expenditure can beregained from quasi-rents that are earned by exploiting patents on the fruits of research.The accumulation of knowledge...

In this paper idiosyncratic uncertainty is introduced in a model of economic growth with an increasing variety of intermediate products. Both the costs of producing intermediate products and their quality are uncertain for all producers at all times. Using the property of the model that the...

Despite the centrality of incentives for innovation in models of economic growth, there is little systematic evidence that the value of technologies varies with market size and institutional arrangements. This paper presents micro-evidence indicating the value of patent rights for a given...

Reduced credit supply in the years 2008 and 2009 should have resulted in lower growth in industries that are more dependent on external finance. This effect should have been stronger in countries with a more prominent and/or more leveraged financial system. We focus on the OECD countries and,...

This paper presents a model of economic growth where products are invented and patented, and where production involves fixed costs at the location of the plant. The model is used to assess the effects of instantaneous integration of a small, autarkic country into a larger economy on a) consumer...

In GRAVITY WITH GRAVITAS: A SOLUTION TO THE BORDER PUZZLE, Anderson and Van Wincoop (2003) estimate what trade between US states and Canadian provinces would have been if the border between Canada and the United States had not existed. They showed that computing the border effect requires...