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Paul Novosad and the Development Data Lab (devdatalab) built and open-sourced a…

2026-07-15 · 13:38 UTC ·@bswud ·0 min read

Brief

Paul Novosad (devdatalab) released an open dataset of boundaries for over 10,000 global cities, addressing a surprising gap in research infrastructure. The author warns that relying on administrative borders (for example, Paris within the périphérique versus Greater London) misleads comparisons and urges adding time-series data on population, GDP, and evolving boundaries to answer deeper urban questions.

Why it matters

Paul Novosad and the Development Data Lab (devdatalab) built and open-sourced a usable set of boundaries for 10,000+ global cities because no single dataset existed.

Key details

  • Author highlights that administrative boundaries distort city comparisons (e.g., Paris inside the périphérique vs Greater London) and calls for adding population over time, GDP over time, and boundaries over time to enable better research.
Source evidence

Wow, incredible work. The flaws in using administrative boundaries to compare cities become obvious every time someone compares Paris inside the periphery road to Greater London. Now all we need is to add data on population (over time), GDP (over time), boundaries (over time), and we can start answering some amazing questions!

Paul Novosad (@paulnovosad)

We couldn’t find a usable set of boundaries for 10,000+ global cities, so we (@devdatalab) developed our own and made them open for research.

We were kind of shocked this didn’t exist already. A thread 1/

— https://nitter.net/paulnovosad/status/2077372221996044423#m