Fig. 1: Definition of a jam tree.
From: Unveiling city jam-prints of urban traffic based on jam patterns
a Examples of several jam trees. Each directed link represents a road segment (indicated by an upper case letter), with an arrow indicating the direction of traffic flow on it. The number above each link indicates its jam duration, i.e., number of successive time intervals of traffic jam. Here, each time interval represents 10 min. If the difference in jam duration between two adjacent segments is less than a threshold (in the present study 2 intervals, i.e., 20 min), they are considered part of the same jam tree31. b Key information about the presented jam trees in (a). The table presents information of each jam tree, including its trunk, size, and cost. Each jam tree has only a single specific trunk based on the above definition. The size of a jam tree is determined by the number of segments that belong to it, including both the main trunk and associated branches, while the temporal cost of each jam tree is defined as the weighted sum cost of its trunk and branches (See Methods).
