Individual bias and fluctuations in collective decision making: from algorithms to Hamiltonians.

In this paper, we reconsider the spin model suggested recently to understand some features of collective decision making among higher organisms (Hartnett2016038701). Within the model, the state of an agentis described by the pair of variables corresponding to its opinionSi=±1and a biastoward any of the opposing values of. Collective decision making is interpreted as an approach to the equilibrium state within the nonlinear voter model subject to a social pressure and a probabilistic algorithm.

Generalized Ising Model on a Scale-Free Network: An Interplay of Power Laws.

We consider a recently introduced generalization of the Ising model in which individual spin strength can vary. The model is intended for analysis of ordering in systems comprising agents which, although matching in their binarity (i.e.