Graph motifs are used to analyze networks from diverse domains. We consider the problem of counting motifs in bipartite affiliation networks, such as author-paper, user-product, and actor-movie relations. The substantial prior work on counting motifs in unipartite graphs, such as triangle counting, does not apply here, since bipartite graphs do not have triangles. Unlike the solution of project...

It has been observed that mutualistic bipartite networks have a nested structure of interactions. In addition, the degree distributions associated with the two guilds involved in such networks (e.g., plants and pollinators or plants and seed dispersers) approximately follow a truncated power law (TPL). We show that nestedness and TPL distributions are intimately linked, and that any biological ...

We study collaboration networks in terms of evolving, self-organizing bipartite graph models. We propose a model of a growing network, which combines preferential edge attachment with the bipartite structure, generic for collaboration networks. The model depends exclusively on basic properties of the network, such as the total number of collaborators and acts of collaboration, the mean size of ...

Consider an information network with harmful procedures called attackers (e.g., viruses); each attacker uses a probability distribution to choose a node of the network to damage. Opponent to the attackers is the system protector scanning and cleaning from attackers some part of the network (e.g., an edge or a path), which it chooses independently using another probability distribution. Each att...

In this paper, we describe a new model for thinking about implicit social networks, which are defined when users interact by modifying a common shared object. These are also called "knowledge sharing" networks and are in contrast to the typical person-to-person social networks. The properties of these networks are important to many data mining applications including recommendation systems, pers...

We study a setting in which individual players choose their partners as well as a mode of behavior in 2 × 2 anti-coordination games. We characterize the nature of equilibrium network structures as well as study the effects of network structures on individual behavior. Our analysis shows that the structure of the equilibrium networks depends on the value of the cost of forming links. As the cost...