Table 1.

Comparison between the INRIX (12 months) traffic index and the number of hotspots estimated by the proposed model for the most congested cities of the world.

Milano36.2108692414 315
London32.493637814 662
Los Angeles32.257679919 368
Brussels30.550664515 624
Antwerpen28.644653015 252
San Francisco27.945885425 530
Stuttgart21.934833019 946
Nottingham21.628733716 723
Karlsruhe21.319425710 379
  • aThe INRIX index is the percentage increase in the average travel time of a commute above free-flow conditions during peak hours, e.g. an INRIX index of 30 indicates a 40-min free-flow trip will take 52 min. Each city has been mapped to a graph with the indicated numbers of nodes and links. See text for details and electronic supplementary material, figures S1–S18 for the graph representation of the cities and the geographical representation of the congestion hotspots.