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arXiv · 2610.31159

Beyond city pairs: Higher-order information in urban growth across borders

Cillian Hourican·Debraj Roy
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Abstract

We apply higher-order information measures to urban growth across borders and spatial units. We analyse 8,808 functional urban areas using gridded GDP estimates allocated from national accounts. Negative estimated O-information occurs in 29.93% of cross-border triplets and 2.00% of domestic triplets. This fifteen-fold contrast falls to fourfold at comparable dependence strength and persists under data-quality restrictions. Target-specific decompositions show how information overlaps or combines across cities. Administrative subdivisions have mean O-information within matched random-map ranges inside countries. These findings show why interpreting geographic dependence requires specifying comparison cities and spatial units, while economic connections remain to be established independently.

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Cillian Hourican, Debraj Roy. 2026-10-22. Beyond city pairs: Higher-order information in urban growth across borders. https://arxiv.org/abs/2610.31159

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