Figure 2. Smoking behaviour and centrality before and after the social transition.

Panel (a,b) illustrate the initial and the final state of the contact network as simulated by the proposed adaptive network model of behaviour selection. Circles represent individual nodes. Their colour and size represent smoking behaviour and the individual’s centrality, respectively. At the initial state of the simulation (panel (a)), smoking behaviour is homogeneously distributed across the network with random centrality values and the number of smokers equals the number of non-smokers resulting from the initial distribution of smoking dispositions. As the normative support for smoking gradually declined, behaviour and centrality changed over repeated interactions within the network. In the final state of the simulation (panel (b)), the number of smokers has considerably declined. As a consequence of the adaptive network dynamics, the centrality of smokers is selectively reduced. In comparison, non-smokers are characterised by a wide distribution of centrality.