|Rational choice is the label given to a methodology now common across the social sciences: the method of modelling social behaviour on the supposition that individuals are rational agents who optimize subject to constraints. In politics and sociology the rational choice approach is sometimes called public choice, to distinguish collective decisions from the individual or private decisions more characteristically studied in economics. The use of game theory and formal decision theory is very common among social scientists using rational choice methods, but they are best known for their work in four domains of political science.
First, rational choice theorists have examined the logic of voting rules. Controversial discussion still centres on certain alleged paradoxes of collective choice identified in â€˜Arrow\'s theoremâ€™ which demonstrates that no system of voting which seeks to aggregate preferences from knowledge of individual preferences can avoid logical inconsistencies when five apparently reasonable conditions are required not to be violated.
Second, rational choice theorists have explored the logic of treating voters as utility maximizers and political parties as pure office-seeking organizations intent on maximizing their votes. These assumptions have been used to explain the convergence of parties on similar policy platforms in plurality-rule election systems, and the sharp policy-differentiation between parties in proportional representation systems. They have also been used to explore the logic of coalition behaviour.
Third, rational choice theorists have examined the logic of assuming that bureaucrats can be modelled as budget-maximizing individuals, predicting that government services will be â€˜over-suppliedâ€™ and inefficiently supplied because of the monopolistic advantages of bureaucratsâ€”at least as compared with politicians and voters.
Finally, rational choice theorists have examined the extent to which constraints on collective action prevent some interests from getting organized while others find it easy to organize. The product of an interest group is a â€˜public goodâ€™, that is a good which is non-excludable (people will get the benefit from it even if they do not contribute to it) and non-rival (that is, individual consumption of the good is not affected by other people\'s consumption of it). Therefore, it is reasoned, rational individuals may calculate that the benefit they receive from the production of a public good (multiplied by the probability that their contribution will be decisive to the good being advanced) is less than the costs of their contribution. In short, in many cases individuals have the incentive to â€˜free rideâ€™ rather than to contribute towards public goods. This â€˜logic of collective actionâ€™ has been invoked, controversially, to explain many different phenomena, including why some interests are better represented than others in a democracy and why some countries have higher economic growth rates than others.
The critics of rational choice usually condemn it on the grounds that they disagree with the realism of its assumptions. More rarely, but more effectively, critics show how the methodology can be used to make political analyses and predictions at odds with the classical liberalism or libertarianism espoused by most rational choice theorists. BO\'L
Further reading P. Dunleavy, Bureaucracy, Democracy and Public Choice; , J. Elster (ed.), Rational Choice; , L. Lewin, Self-Interest and Public Interest in Western Politics.