Flow of Control in Networks

摘要

Many complex systems can be viewed as networks, in which nodes represent system elements and edges correspond to interactions between those elements. In such networks, a subset of nodes-the driver nodes-can yield control of the entire network when they are driven by external signals (1-3). However, to control a system, one must know not only what parts need to be controlled but also why these particular parts need to be controlled. On page 1373 of this issue, Ruths and Ruths (4) put forward an elegant framework that elucidates the origin of control in networks. The framework divides nodes into three categories based on how they affect the flow of control in networks. This approach gives rise to control profiles that the authors use to classify a host of empirical and synthetic networks. The results suggest that networks from different domains but in the same category may be more similar to one another than previously thought.