We incorporate the behaviour of tax evasion into the standard two-dimensional Ising model and augment it by providing policy-makers with the opportunity to curb tax evasion via an appropriate enforcement mechanism. We find that tax evasion may vary greatly over time if no measures of control are...

Since its introduction in 2000, the Sznajd model has been assumed to simulate a democratic community with two parties. The main flaw in this model is that a Sznajd system freezes in the long term in a non-democratic state, which can be either a dictatorship or a stalemate configuration. Here we...

The 2-spin Ising model in statistical mechanics and the 2×2 normal form game in game theory are compared. All configurations allowed by the second are recovered by the first when the only concern is about Nash equilibria. But it holds no longer when Pareto optimum considerations are introduced...

In this Note a social network model for opinion formation is proposed in which a person connected to q partners pays an attention 1/q to each partner. The mutual attention between two connected persons i and j is taken equal to the geometric mean 1/qiqj. Opinion is represented as usual by an...

Public debates driven by incomplete scientific data where nobody can claim absolute certainty, due to the current state of scientific knowledge, are studied. The cases of evolution theory, global warming and H1N1 pandemic influenza are investigated. The first two are of controversial impact...

We study the survival of extreme opinions in various processes of consensus formation. All the opinions are treated equally and subjected to the same rules of changing. We investigate three typical models to reach a consensus in each case: (A) personal influence, (B) influence from surroundings,...

We study the dynamics of the adoption of new products by agents with continuous opinions and discrete actions (CODA). The model is such that the refusal in adopting a new idea or product is increasingly weighted by neighbor agents as evidence against the product. Under these rules, we study the...

The dynamical origin of opinion polarization in the real world is an interesting topic that physical scientists may help to understand. To properly model the dynamics, the theory must be fully compatible with findings by social psychologists on microscopic opinion change. Here we introduce a...

Moral Foundation Theory states that groups of different observers may rely on partially dissimilar sets of moral foundations, thereby reaching different moral valuations. The use of functional imaging techniques has revealed a spectrum of cognitive styles with respect to the differential...