Employment growth is strongly predicted by smaller average establishment size, both across cities and across industries within cities, but there is little consensus on why this relationship exists. Traditional economic explanations emphasize factors that reduce entry costs or raise...

The decade of the 1940s was one of the darkest periods in the country's history, with years of famine, repression, general misery, and impoverishment of all aspects of national life ranging from culture to the economy. During those years plans were made to establish a Spanish motor industry once...

We provide the first measurement of knowledge spillovers from venture capital-financed companies onto the patenting activities of other companies. On average, these spillovers are nine times larger than those generated by the R&D investment of established companies. Spillover effects are larger...

Do contributions to online content platforms induce a feedback loop of ever more user-generated content or will they discourage future contributions? To assess this, we use a randomized field experiment which added content to some pages in Wikipedia while leaving similar pages unchanged. We find...

Policy makers are increasingly concerned about the combination of market power and massive data collection in digital markets. This concern is fueled by the theoretical prediction that more market power causes firms to collect ever more data from their users. We investigate the relationship...

Much of today’s software relies on programming code shared openly online. Yet, it is unclear why volunteer developers contribute to open-source software (OSS), a public good. We study OSS contributions of some 22,900 developers worldwide on the largest online code repository platform, GitHub,...

We analyze whether an informal second channel for communication can improve the efficiency of knowledge transfer in an electronic network of practice. We explore this question by analyzing the effect of chat rooms in the well-known Q&A forum Stack Overflow. We identify the causal effect using a...

We analyze the relationship between unemployment and the supply of online labor for microtasking. Using detailed US data from a large microtasking platform between 2011 and2015, we study the participation and the number of hours supplied by workers in the US.We find that more individuals...

This paper presents an Optimised Search Heuristic that combines a tabu search method with the verification of violated valid inequalities. The solution delivered by the tabu search is partially destroyed by a randomised greedy procedure, and then the valid inequalities are used to guide the...

To understand whether retailers should consider consumer returns when merchandising, we study how the optimal assortment of a price-taking retailer is influenced by its return policy. The retailer selects its assortment from an exogenous set of horizontally differentiated products. Consumers...