Following are the most recent versions of the articles in this review.
City Scaling
- Cities and Wellbeing. The mixed research on how mental health and wellbeing is affected by the urban form. Updated February 13, 2026.
- Pace of Life. Certain pace of life metrics, such as walking speed and cell phone call volume, tend to be higher in larger cities. Updated January 30, 2026.
- City Size and Crime. How and why crime rates in a city generally increase with city size. Updated March 29, 2025.
- Urban Scaling. How a city’s wealth increases as the city grows. Updated December 20, 2024.
Theory of City Scaling
- Standard Urban Model. The basic Alonso-Muth-Mills model, or the standard urban model, works well in predicting how cities grow despite its limitations. Updated December 27, 2025.
- Polycentricity. An urban development methodology that distributes population and urban functions throughout a region, rather than concentrating them. Updated November 22, 2025.
- Zipf’s Law. The regular rank/size relationship in the cities of a country. Updated July 26, 2025.
- Marchetti’s Constant. The observation that a city is typically defined by a 30 minute commute radius around a central business district. Updated July 5, 2025.
- Sources of Agglomeration. The mechanisms by which larger cities drive increased prosperity. Updated December 7, 2024.
Urbanism
- Transportation Technology. How emerging transportation technologies might change the socioeconomic performance of cities. Updated December 20, 2025.
- Car-Free Cities. The environmental, health, and economic impact of superblocks and other urban design principles to reduce automobile usage. Updated December 6, 2025.
- The Rebound Effect. The tendency for total driving to increase after transportation efficiency improvements, such as new road lanes, remote work, public transportation, and compact neighborhoods. Updated August 1, 2025.
Economic Growth
- Business Scaling. Larger companies face both advantages in terms of economies of scale and scope and disadvantages with the costs of hierarchy. Updated October 25, 2025.
- Demographic Transition. The tendency for birth rates to decline with economic development. Updated October 10, 2025.
- Population and Economic Growth. The role of population in driving long-term economic growth. Updated June 7, 2025.
- Energy and Economic Growth. The importance of energy consumption as a driver of economic growth. Updated May 24, 2025.
Origins of Cooperation
- The Expansion of Cooperation in the Neolithic. How large-scale cooperation expanded after the development of agriculture. Updated May 8, 2026.
- Cooperation in the Paleolithic. Large scale cooperation occurred before agriculture, but it seems to have been rare. Updated May 8, 2026.
- Cooperation in Nonhuman Animals. Large scale cooperation between unrelated groups of nonhuman animals is rare. Updated April 10, 2026.
- Dunbar’s Number. The claim that, due to the difficult to managing social relationships, human communties based on interpersonal knowledge are limited to around 150 people. Updated August 16, 2025.
Sustainability
- Scale and Existential Risk. Whether scale creates a risk of a catastrophe that would theaten civilization. Updated August 29, 2025.
- Theoretical Limits to Growth. A review of estimated limits to the number of people who could live on Earth and beyond. Updated March 7, 2025.
- Scale and Ecological Collapse. Ways in which growing social scale might post a risk of harmful ecological collapse. Updated February 15, 2025.
- Resource Shortages. Understanding how mineral resources are characterized and why the world is unlikely to run out of a major commodity in the foreseeable future. Updated February 7, 2025.
- IPAT and its Variants. A simple model of how an environmental impact varies with changes in population, affluence, and technology. Updated January 31, 2025.
- Limits to Growth. Resource and sustainability challenges that might curtail growth and scaling. Updated January 17, 2025.