Figure 1

Illustration of some node types and connectivity patterns. (A) Some of the node types with the vector representations. The highlighted node with a shadow boundary is the ego node. A bus stop is a solid black dot marked with “b” and a subway station is a hollow dot with “s”. Depending on its connection with other nodes, the ego node can be (from top-left to bottom-right): a non-bus non-subway point (O/D), a bus non-transfer stop, a bus transfer stop, a subway non-transfer station, a subway transfer station, both a bus stop and a subway station (b/s), a bus stop and a subway transfer station, a bus transfer stop and a subway station, a bus transfer stop and a subway transfer station. The vector encodes different types of nodes. See Methods for details. (B) Some examples of the connectivities of different node types: a bus stop and a subway station connected by walking (dash red line), a bus stop and a subway station connected by bus (solid red line) and walking (dash red line), a subway non-transfer station and a subway transfer station connected by subway. The links are weighted by travel mode and distance with continuous numerical values, which makes it impossible to draw motifs in conventional sense.