2.4.1 Causal fidelity
Some paths existing between nodes in the static aggregation do not follow a chronological order, and therefore such paths do not exist in the temporal representation. To quantify the quality of a static aggregation, Lentz et al. (2013) defined so-called causal fidelity, which measures the proportion of paths in a temporal network which exist in the static counterpart. For this purpose, accessibility matrices are constructed for the static and temporal networks representing the path lengths between each pair of nodes. To calculate the causal fidelity of the network, it is necessary to calculate thepath density (equation 4), where we defined the density of its accessibility matrix: