Effects of Interaction Range on the Behavior of Opinion Consensus

We have frequently encountered the rapid changes that prevalent opinion of the social community is toppled by a new and opposite opinion against the pre-exiting one. To understand this interesting process, mean-field model with infinite-interaction range has been mostly considered in previous studies S. A. Marvel et al., Phys. Rev. Lett. 110, 118702 (2012). However, the mean-field interaction range is lack of reality in the sense that any individual cannot interact with all of the others in the community. Based on it, in the present work, we consider a simple model of opinion consensus so-called basic model on the low-dimensional lattices (d = 1, 2) with finite interaction range. The model consists of four types of subpopulations with different opinions: A, B, AB, and the zealot of A denoted by A_c, following the basic model shown in the work by S. A. Marvel et al. Comparing with their work, we consider the finite range of the interaction, and particularly reconstruct the lattice structure by adding new links when the two individuals have the distance < σ. We explore how the interaction range σ affects the opinion consensus process on the reconstructed lattice structure. We find that the critical fraction of population for A_c required for the opinion consensus on A shows different behaviors in the small and large interaction ranges. Especially, the critical fraction for A_c increases with the size of σ in the region of small interaction range, which is counter-intuitive: When the interaction range is increased, not only the number of nodes affected by A_c but also that affected by B grows, which is believed to cause the increasing behavior of the critical fraction for A_c. We also present the difference of dynamic process to the opinion consensus between the regions of small and large interaction ranges.