Local Convergence and Global Diversity: From Interpersonal to Social Influence

How can minority cultures resist assimilation into a global monolith in an increasingly "small world"? Paradoxically, Axelrod found that local convergence can actually preserve global diversity if cultural influence is combined with homophily, the principle that "likes attract." However, follow-up studies showed that this diversity collapses under random cultural perturbation. The authors discovered a new source of this fragility-the assumption in Axelrod's model that cultural influence is interpersonal (dyadic). The authors replicated previous models but with the more empirically plausible assumption that influence is social-people can be simultaneously influenced by several network neighbors. Computational experiments show that cultural diversity then becomes much more robust than in Axelrod's original model or in published variations that included either social influence or homophily but not both. The authors conclude that global diversity may be sustained not by cultural experimentation and innovation but by the ability of cultural groups to discourage those activities.