What does society mean? Is it only the sum of individuals? As you are probably thinking, the answer is no. Society means more than just the sum of individuals because humans are interacting beings. And what about opinions? How does an opinion spread in a society?
There are many models to study opinion formation as an example of collective social behavior. One of them is the voter model, which is based on the mechanism of random imitation, also known as herding behavior in some situations. It is a very simple model used for studying the evolution of a group of individuals with two possible opinions (might be liberal or conservative). Each individual is treated as a node in a network, and it has a value +1 (yellow) or -1 (blue) depending on her opinion. The dynamical rules of evolution are the following:
The next video is a representation of one step of the process:
A finite group of people will reach a state of consensus at some point. This implies that all of them end up having the same opinion. The time needed for this to occur (consensus time) depends on number of voters and on the voters’ relationships, that is how they are all connected.
The voter model isolates a single mechanism of social interaction, imitation, and explores its consequences. In a real social system several different mechanisms of social interaction occur simultaneously.
The following video is a computer simulation of the voter model for a group of 100 people. Initially, there is the same number of individuals with each of the two possible opinions. In the end, they reach a consensus absorbing or frozen state