Earth at night. New research shows a marked economic benefit in cities that share strong interconnectivity. (image: NASA)

As city population grows, so does violent crime, contagious diseases, and per-capita GDP. A significant body of research has investigated what drives this scaling relationship, examining factors within a city.

A new paper in PNAS Nexus looks much farther afield. The authors find that cities connected strongly to other cities through multinational firms like financial institutions, consulting and law firms, accountants, and media organizations show a marked economic benefit, even beyond normal scaling.

The paper was co-authored by former SFI Omidyar Fellow Vicky Chuqiao Yang (MIT), SFI Professor Christopher Kempes, and Jacob Jackson, a 2019 Undergraduate Complexity Research participant at SFI, and compares 255 urban areas in the European Union, United States, and China.

Their analysis shows that increased global connectivity is associated with increased GDP. To rule out more homegrown factors at play, the authors report that global connectivity does not affect a city’s rates of homicide, which is likely largely local in cause. With more than half the world’s population living in urban areas, it pays to study links between cities, rather than solely local socioeconomic connections.

Read the paper “Inter-city firm connections and the scaling of urban economic indicators” in PNAS Nexus (November 9, 2024). DOI: 10.1093/pnasnexus/pgae503