Artículos con la etiqueta ‘Teoría de juegos’

Selection and Influence in Cultural Dynamics

Por • 6 may, 2013 • Category: sociologia

One of the fundamental principles driving diversity or homogeneity in domains such as cultural differentiation, political affiliation, and product adoption is the tension between two forces: influence (the tendency of people to become similar to others they interact with) and selection (the tendency to be affected most by the behavior of others who are already similar). Influence tends to promote homogeneity within a society, while selection frequently causes fragmentation. When both forces are in effect simultaneously, it becomes an interesting question to analyze which societal outcomes should be expected.



How hard is it to control an election by breaking ties?

Por • 29 abr, 2013 • Category: sociologia

We study the computational complexity of the problem of controlling the result of an election by breaking ties. When the chair is only asked to break ties to choose between one of the co-winners, the problem is trivially easy. However, in multi-round elections like STV, we prove that it can be NP-hard for the chair to compute how to break ties to ensure a given result. Our results contain several surprises. For example, whilst it is NP-hard to compute a manipulating vote for a multi-round rule like Nanson, it is polynomial for the chair to control the result by breaking ties. As a second example, it can be NP-hard to control an election by breaking ties even with a simple two-stage voting rule.



Paradoxes in Social Networks with Multiple Products

Por • 4 feb, 2013 • Category: Opinion

Recently, we introduced in arXiv:1105.2434 a model for product adoption in social networks with multiple products, where the agents, influenced by their neighbours, can adopt one out of several alternatives. We identify and analyze here four types of paradoxes that can arise in these networks. To this end, we use social network games that we recently introduced in arXiv:1211.5938. These paradoxes shed light on possible inefficiencies arising when one modifies the sets of products available to the agents forming a social network. One of the paradoxes corresponds to the well-known Braess paradox in congestion games and shows that by adding more choices to a node, the network may end up in a situation that is (weakly) worse for everybody.



The Monty Hall Problem in the Game Theory Class

Por • 12 jul, 2011 • Category: Opinion

The basic Monty Hall problem is explored to introduce into the fundamental concepts of the game theory and to give a complete Bayesian and a (noncooperative) game-theoretic analysis of the situation. Simple combinatorial arguments are used to exclude the holding action and to find minimax solutions.



The Monty Hall Problem: Switching is Forced by the Strategic Thinking

Por • 25 mar, 2011 • Category: Opinion

Game versions of the Monty Hall Problem are discussed. The focus is on the principle of eliminating the dominated strategies, both in the zero-sum and noncooperative formulations.



The Joker effect: cooperation driven by destructive agents

Por • 22 mar, 2011 • Category: sociologia

The appearance of jokers promotes a rock-paper-scissors dynamics, where jokers outbeat defectors and cooperators outperform jokers, which are subsequently invaded by defectors. Thus, paradoxically, the existence of destructive agents acting indiscriminately promotes cooperation.



Computability of simple games: A complete investigation of the sixty-four possibilities

Por • 1 mar, 2011 • Category: Educacion

Classify simple games into sixteen «types» in terms of the four conventional axioms: monotonicity, properness, strongness, and nonweakness.