Based on Inversity : Leveraging the Friendship Paradox in Unknown Network Structures

Network intervention problems benefit from selecting a more connected node, which is more likely to result in stronger indirect effects. However, in many network contexts, the structure of the network is unknown. We derive and examine the mathematical properties of two distinct “informationally light” strategies, a global strategy and local strategy, that yield higher degree nodes in virtually any network structure. These strategies are based on the friendship paradox: “your friends have more friends that you do.” We further identify a novel network property called Inversity, which connects the fundamental parameters of these two strategies. We prove that the sign of Inversity for any given network determines which of the two strategies will be most effective in that network. We assess the performance of these strategies across a wide range of generative network models and real networks, and we show how to leverage network structure through these strategies even when the network structure is unknown.