We identify the impact of local firm concentration on incumbent performance with a quasi natural experiment. When Germany was divided after World War II, many firms in the machine tool industry fled the Soviet occupied zone to prevent expropriation. We show that the regional location decisions...

Modern metropolitan areas involve large concentrations of economic activity and the transport of millions of people each day between their residence and workplace. We use the revolution in transport technology from the invention of steam railways, newly-constructed spatially-disaggregated data...

This article reviews recent literature using insights from history to answer central questions in urban economics. This area of research has seen rapid growth in the past decade, thanks to new technologies that have made available increasingly rich data stretching far back in time. The focus is...

A growing theoretical literature emphasizes the role that leaders play in shaping beliefs and social norms. We provide empirical evidence for such 'civic leadership.' We focus on the Forty-Eighters, a group of political refugees from Germany's failed 1848 revolutions, and their role in the...

This paper estimates the value of urban trees. The empirical strategy exploits an ecological catastrophe -- the Emerald Ash Borer (EAB) infestation in Toronto to isolate exogenous variation in neighborhood tree canopy changes. Adding one tree to a postcode increases property prices by 0.40%; the...

Instrumental variables (IV) are a common means to identify treatment effects. But standard IV methods do not allow us to unpack the complex treatment effects that arise when a treatment and its outcome together cause a second outcome of interest. For example, IV methods have been used to show...

Shale gas has grown to become a major new source of energy in countries around the globe. While its importance for energy supply is well recognized, there has also been public concern over potential risks such as damage to buildings and contamination of water supplies caused by geological...

We identify the causal effect of trade-integration with China and Eastern Europe on voting in Germany from 1987 to 2009. Looking at the entire political spectrum, we find that only extreme-right parties respond significantly to trade integration. Their vote share increases with import...

How do communication costs affect the production of new ideas and inventions? To answer this question, we study the introduction of the Uniform Penny Post in Great Britain in 1840. This reform replaced the previous system of expensive distance-based postage fees with a uniform low rate of one...

Did overseas slave-holding by Britons accelerate the Industrial Revolution? We provide theory and evidence on the contribution of slave wealth to Britain's growth prior to 1835. We compare areas of Britain with high and low exposure to the colonial plantation economy, using granular data on...