Data, modelling and inference in road traffic networks.

In this paper, we study UK road traffic data and explore a range of modelling and inference questions that arise from them. For example, loop detectors on the M25 motorway record speed and flow measurements at regularly spaced locations as well as the entry and exit lanes of junctions. An exploratory study of these data helps us to better understand and quantify the nature of congestion on the road network. From a traveller's perspective it is crucially important to understand the overall journey times and we look at methods to improve our ability to predict journey times given access jointly to both real-time and historical loop detector data. Throughout this paper we will comment on related work derived from US freeway data.