The diffusion of knowledge in the world generates positive externalities if knowledge flows increase the productivity of R&D. Our work analyzes knowledge diffusion and knowledge externalities in generating innovation and in determining productivity. We first estimate the determinants of...

We document the spatial diffusion of Friedrich Froebel's radical invention of kindergartens in 19th-century Germany. The first kindergarten was founded at Froebel's birthplace. Early spatial diffusion can be explained by cultural proximity, measured by historical dialect similarity, to Froebel's...

In this article we estimate the long-run aggregate elasticity of substitution between skilled and unskilled workers. This is an important parameter as it allows us to compute the skill biased technological progress (SBTP) from the evolution of relative wages. However, it is hard to estimate...

We estimate the impact of the Covid-induced shift to working from home (WFH) on offline consumer spending within cities. The analysis builds on a postcode-level panel (2019–2023) of novel cellphone mobility and payment card transaction data for 50 German metropolitan areas (MAs)....

In the nineties, average firm size decreased, organisations decentralized, and workers preferences shifted from large to small firms. Our model identifies the economic forces behind this trend. Small firms with little capital at risk are subject to risk-shifting. They realize more of their...

A novel method is applied to evaluate the effect of capital constraints on entrepreneurial performance on a panel of 1,000 Dutch entrepreneurs. We find that initial capital constraints hinder entrepreneurs in their performance, even when we control for various human capital and other factors...

Diversified firms often trade at a discount with respect to their focused counterparts. The literature has tried to explain the apparent misallocation of resources with lobbying activities or power struggles. We show that diversification can destroy value even when resources are efficiently...

We show that the recent rise in Afghan opium production is caused by violent conflicts. Violence destroys roads and irrigation, crucial to alternative crops, and weakens local incentives to rebuild infrastructure and enforce law and order. Exploiting a unique data set, we show that Western...

This paper studies empirically the effects of and the interactions amongst economic and political liberalizations. Economic liberalizations are measured by a widely used indicator that captures the scope of the market in the economy, and in particular of policies towards freer international...