The papers in this issue are selected from the VI Dyses Conference (Dyses 2010) held in Benevento, Italy, in September 2010, and this conference brought together scientists from different areas such as mathematics, physics, social sciences, economy, law, biology, informatics, as well as people working on social inequality, social welfare, collective tendencies, cognition and economy, among others.
The primary contributors at Dyses 2010 focused on how to prospect and evaluate social and economical situations in future; the processes of decision making and assessments of socioeconomic decisions have been widely investigated. Approaches to the legal framework are more adequate to grant peaceful interactions among individuals, societies, and countries as well as criteria of confidence of prognosis, decision, and uncertainty have been analyzed in the information and knowledge society contexts.
The full papers of contributors presented at VI Dyses Conference are published in several international journals, In particular, we warmly thank Ron R. Yager for his decision to host this special issue of International Journal of Intelligent Systems. Some selected papers are dedicated to the application of the game theoretical approach to economical systems and analysis of aggregation laws in this context.
In particular, as far as game-theoretical approach is concerned, E. D'Amato, E. Daniele, L. Mallozzi, and G. Petrone in "Equilibrium strategies via GA to Stackelberg games under multiple follower's best reply" study a two-person game between one leader and one follower, called the Stackelberg game. The lead player announces a decision before the others, and the follower takes into account this decision and solves an optimization problem that may have multiple solutions. Then, the leader optimizes his objective by assuming a given follower's reaction depending on his behavior. Then, a hierarchical equilibrium solution for a two-level game is considered, particularly the strong Stackelberg solutions that correspond to an optimistic leader's point of view; a numerical procedure based on a genetic algorithm (GA) evolution process to compute them is presented. The use of a multimodal GA allows us to