Structure and schematic dynamics of the two networks considered in Palla et. al., Nature 446, 664 (2007) (this is Figure 1 from the paper). (a) The coauthorship network . The figure shows the local community structure at a given time step in the vicinity of a randomly selected node. (b) As (a) but for the phonecall network. (c) The filled black symbols correspond to the average size of the largest subset of members with the same zipcode, <n_{real}>, in the phonecall communities divided by the same quantity found in random sets, <n_{rand}>, as a function of the community size, s. Similarly, the open symbols show the average size of the largest subset of community members with an age falling in a threeyear time window, divided by the same quantity in random sets. The error bars in both cases correspond to <n_{real}> / ( <n_{rand}> + σ_{rand}) and <n_{real}> / ( <n_{rand}>  σ_{rand}) where σ_{rand} is the standard deviation in the case of the random sets. (d) The <n_{real}>/s as a function of s, for both the zipcode (filled black symbols) and the age (open symbols). (e) Possible events in community evolution. (f) The identification of evolving communities. The links at t (blue) and the links at t+1 (yellow) are merged into a joint graph (green). Any CPM community at t or t+1 is part of a CPM community in the joined graph, so these can be used to match the two sets of communities.
