Nested economies of scale in global city mass
Kangning Huang, Mingzhen Lu
At the neighborhood scale, doubling population density only increases built mass by about 68% (δ ≈ 0.75) — economies of scale intensify inside the city versus city-level scaling (β ≈ 0.90)
- At the neighborhood scale, doubling population density only increases built mass by about 68% (δ ≈ 0.75) — economies of scale intensify inside the city versus city-level scaling (β ≈ 0.90)
- Analyzes over 3,000 cities globally to reveal universal sub-linear scaling of built mass with population, with a city-level scaling exponent of β ≈ 0.90 meaning larger cities use less built mass per capita
- Proposes a theoretical framework showing that city-level sub-linear scaling emerges from the aggregation of within-city neighborhood-level disparities, establishing a nested multi-scale scaling relationship
- Redefines 'over-built' and 'under-built' conditions as deviations from expected scaling patterns, linking excess built mass to environmental impact and deficient built mass to inadequate living standards


