About
Who runs this project, how to cite it, reuse its data or contribute.
1.The project
A few streets apart, the air, the heat and the time it takes to see a doctor are not the same. Underlaid brings together scattered public data to make these gaps visible, neighbourhood by neighbourhood, from an address and depending on how each person gets around. The site describes; it does not rank residents.
Underlaid is an independent project by Jehanne Dussert, trained in law and computer science, now an expert in artificial intelligence governance.
A former Entrepreneur d'Intérêt Général, a programme of the French interministerial digital directorate (DINUM, Prime Minister's services), she led the development of TwinCity, a generator of synthetic 3D images built from a digital twin of Paris to test the biases of computer-vision algorithms. Who is represented in data, and who is not, was already at the heart of her work. Underlaid carries that thread on.
A personal project, run in her free time, unrelated to her employer. It receives no funding, shows no advertising and supports no party or candidate.
2.Cite this work
For an article, a report, a thesis or a presentation:
Dussert, J. (2026). Underlaid: cumulative environmental exposure in Paris and its inner suburbs (version 0.2.0) [data and software]. Zenodo. https://doi.org/10.5281/zenodo.23101510
To always point to the latest version: https://doi.org/10.5281/zenodo.23083312
3.Reuse the data and code
The neighbourhood indicators, the code and the detailed method are public. Every reuse must cite Underlaid and the original sources.
| What | Licence | What it allows |
|---|---|---|
| Code | MIT | Reuse, modify and redistribute the code, including commercially, keeping the licence notice. |
| Neighbourhood indicators | ODbL | Reuse, including commercially, citing the source; derived databases must stay under the same licence (an obligation inherited from OpenStreetMap and City of Paris data). |
| Data from OpenStreetMap | ODbL | Reuse citing "© OpenStreetMap contributors"; derived databases stay under the same licence. |
| Maps and visuals of the site | CC BY 4.0 | Reuse a map or a screenshot citing "Underlaid" and the data source. |
4.Collaborate
Researchers, associations, local authorities, public servants: all proposals are welcome, in particular to:
- report an error or a more reliable source;
- check the figures of an area you know well;
- test wheelchair or slow-walking trips on the ground;
- extend the map to other areas.
5.Press
Key figures are checked and dated. Please cite the version and do not present neighbourhoods as "the worst": the site places, it does not rank residents.
6.Your data
The address you type is sent to the Base adresse nationale (a public service) to find your neighbourhood; Underlaid neither keeps it nor puts it in the page address. The site uses neither cookies nor audience measurement. Your language choice is kept in your browser, and the code of the last neighbourhood viewed is kept in the tab for the visit. The host (Vercel) keeps technical access logs.