Work on urban mobility, segregation, labor markets and digital twins of society.
Schools sit in neighbourhoods of their own. Treating clusters of nearby schools as a network, an entropy measure lets school and residential segregation be compared on the same spatial footing, a long-standing problem left methodologically open.
R. M. Hilman, W. Botterman, and M. Lees. Under review.
Manuscript in reviewDoes a bigger patch of city hold a more diverse economy? Mapping firms and sectors as a bipartite network across grid scales in Manhattan, we find diversity is carried by the largest sectors, whose many firms knit the densest connections.
R. M. Hilman. Under review.
Manuscript in reviewWhat we search for online and where we go offline are two halves of one behavioural loop. Linking them in Budapest, we find digital exploration is more repetitive than physical movement, and COVID-19 broke spatial routines more than cognitive ones.
R. M. Hilman and J. A. Koltai. arXiv, Social and Information Networks / Physics and Society, 2026.
Read paperAI is not homogenizing work. Across job ads from ten countries, skills like Python, SQL and machine learning fuse a technical core of occupations while that core pulls away from the rest of the labor market: convergence within, divergence between.
R. M. Hilman and J. A. Koltai. arXiv, Social and Information Networks / Physics and Society, 2026.
Read paperLockdown pushed New Yorkers to travel among neighbourhoods of their own income level, raising the income assortativity of trips from 0.41 to 0.49. Adding streets, buildings and transit to the classic gravity model sharpens flow prediction, and destinations’ pull outweighs origins’ push.
R. M. Hilman. Computational Urban Science, vol. 5(63), 2025.
Read paperCan growing island economies make shipping cheaper? A system dynamics model of eastern Indonesia shows that 7.5% economic growth lifts port cargo throughput by 2%, pointing to logistics centers near the islands as a lever on maritime costs.
C. Amin, A. W. Hasyim, M. Sunan, R. M. Hilman, and H. Fahmiasari. Transportation Research Interdisciplinary Perspectives, vol. 27(101195), 2024.
Read paperLockdowns did not just keep people home; they sorted them. In Bogotá, Jakarta, London and New York, mobility segregation rose with the first lockdowns, and mixing between socioeconomic groups had not recovered weeks after restrictions ended.
R. M. Hilman, M. Garcia-Herranz, V. Sekara, and M. Karsai. arXiv, Social and Information Networks / Physics and Society, 2023.
Read paperPeople mostly visit places of their own class, and when they cross, they go up. In the 20 largest US cities this “upwards bias” strengthens with status, tracks racial residential segregation, and makes everyday mobility more segregated than system-level data suggest.
R. M. Hilman, G. Iñiguez, and M. Karsai. EPJ Data Science, 11(32), 2022.
Read paperPhones, sensors and apps now record how people move in fine detail. This chapter asks what it takes to turn these new data forms into sustainable transport policy: access, bias correction, integration with traditional sources, and ethics.
S. M. Grant-Muller, M. Abdelrazek, H. Budnitz, C. D. Cottrill, F. Crawford, C. F. Choudhury, T. Cunningham, R. M. Hilman, G. Harrison, F. C. Hodgson, J. Hong, A. Martin, O. O’Brien, C. Papaix, and P. Tsoleridis. International Encyclopedia of Transportation (Elsevier), pp. 135–141, 2021.
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