×

Network topology inference using information cascades with limited statistical knowledge. (English) Zbl 1470.94065

Summary: We study the problem of inferring network topology from information cascades, in which the amount of time taken for information to diffuse across an edge in the network follows an unknown distribution. Unlike previous studies, which assume knowledge of these distributions, we only require that diffusion along different edges in the network be independent together with limited moment information (e.g. the means). We introduce the concept of a separating vertex set for a graph, which is a set of vertices in which for any two given distinct vertices of the graph there exists a vertex whose distance to them is different. We show that a necessary condition for reconstructing a tree perfectly using distance information between pairs of vertices is given by the size of an observed separating vertex set. We then propose an algorithm to recover the tree structure using infection times whose differences have means corresponding to the distance between two vertices. To improve the accuracy of our algorithm, we propose the concept of redundant vertices, which allows us to perform averaging to better estimate the distance between two vertices. Though the theory is developed mainly for tree networks, we demonstrate how the algorithm can be extended heuristically to general graphs. Simulations using synthetic and real networks and experiments using real-world data suggest that our proposed algorithm performs better than some current state-of-the-art network reconstruction methods.

MSC:

94A15 Information theory (general)
05C82 Small world graphs, complex networks (graph-theoretic aspects)
62H12 Estimation in multivariate analysis