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.
| city | INRIXa | hotspots | nodes | links |
|---|---|---|---|---|
| Milano | 36.2 | 108 | 6924 | 14 315 |
| London | 32.4 | 93 | 6378 | 14 662 |
| Los Angeles | 32.2 | 57 | 6799 | 19 368 |
| Brussels | 30.5 | 50 | 6645 | 15 624 |
| Antwerpen | 28.6 | 44 | 6530 | 15 252 |
| San Francisco | 27.9 | 45 | 8854 | 25 530 |
| Stuttgart | 21.9 | 34 | 8330 | 19 946 |
| Nottingham | 21.6 | 28 | 7337 | 16 723 |
| Karlsruhe | 21.3 | 19 | 4257 | 10 379 |
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.