Collective Social Dynamics and Social Norms

How individual behaviour is determined or at least influenced by social norms is one of the classic questions of social theory. We consider a norm as a rule guiding individual decisions concerning rituals, beliefs, traditions, and routines. Whenever coordinated behaviour is enforced without the help of an authority, this may be due to social norms. The individual being in the situation of taking a decision at the micro level is guided by social norms imposed at the macro level. The set of all individual decisions in a society generates the macro level behaviour of the system which may strengthen or weaken the existing social norms. Thus, the long run development of social norms is the result of collective dynamics within a social network. We use an agent based simulation model to investigate the emergence, stability, and replacement of social norms within a population of artificial agents. A social network connecting the agents serves to communicate the social norms and the actual behaviour among the agent population. The agents in the network possess two types of links connecting them with their ingroup and with their outgroup, respectively. Agents have the desire to be associated and accepted by the members of their ingroup and they want to be different from the members of their outgroup. Consequently, they derive a utility from adhering to the social norm of their ingroup and from deviating from the social norm of their outgroup. Agents may adopt their behaviour according to the norms given by their ingroup and outgroup. Thus, our model explains under what conditions social norms prevail within a subgroup of the society or even become global norms being respected within the whole population.