Complex systems science is a rather new discipline that has recently gained particular attention in several domains such as economy, biology, computer science, physics, and chemistry. To quote Stephen Hawking, “Complexity is the science of the 21st century” [5]. The idea of complex systems is captured precisely by Aristotle's Metaphysics, in which he remarkably describes “the whole [as] more than the sum of its parts” [11]. In fact, the collective behavior of a complex system cannot be inferred by merely looking at the behavior of the simple parts. What is interesting is looking at the interactions and relationships between the parts that give rise to the collective behavior.
The concept of complexity is connected to the notion of edge of chaos [6], a region in the state space of a system between complete order (i.e., periodic or no change) and total randomness or...