Diffusion and cascading behavior in random networks

The spread of new ideas, behaviors or technologies has been extensively studied using epidemic models. Here we con-sider a model of diffusion where the individuals ’ behavior is the result of a strategic choice. We study a simple coor-dination game with binary choice and give a condition for a new action to become widespread in a random network. We also analyze the possible equilibria of this game and identify conditions for the coexistence of both strategies in large connected sets. Finally we look at how can firms use social networks to promote their goals with limited informa-tion. Our results differ strongly from the one derived with epidemic models and show that connectivity plays an am-biguous role: while it allows the diffusion to spread, when the network is highly connected, the diffusion is also limited by high-degree nodes which are very stable