Urban density boosts productivity and innovation, improves access to goods and services, reduces typical travel distances, encourages energy-efficient construction and transport, and facilitates sharing scarce amenities. However, density is also synonymous with crowding, makes living and moving in cities more costly, and concentrates exposure to pollution and disease. We explore the appropriate measurement of density and describe how it is both a cause and a consequence of the evolution of cities. We then discuss whether and how policy should target density and why the trade-off between its pros and cons is unhappily resolved by market and political forces.

中文翻译：

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城市密度经济学

城市密度提高了生产力和创新能力，改善了获得商品和服务的机会，缩短了典型的出行距离，鼓励了高能效的建筑和运输，并促进了共享稀缺的便利设施。但是，密度也是拥挤的代名词，使城市的生活和迁徙成本更高，并使人们更容易受到污染和疾病的影响。我们探索对密度的适当度量，并描述它是城市发展的原因和结果。然后，我们讨论政策是否以及应该如何针对密度，以及为什么市场和政治力量无法令人满意地解决其利弊之间的取舍。