ECONOMY

912 economic methods in political theory
out that elections are remarkably efficient at aggregating information; Feddersen and
Pesendorfer (1996) prove a striking full-information equivalence theorem for twocandidate
elections with costly voting under any majority or super-majority rule shy
of unanimity, namely despite the fact that a significant proportion of the electorate
might abstain, the limiting outcome as the population grows is almost surely the
outcome that would arise if all individuals voted under complete information. 15
4 Conclusion
.............................................................................
To all intents and purposes, the methods of contemporary positive political theory
coincide with the methods of contemporary economic theory. The most widespread
framework for models of campaign contributions at present derives from the common
agency problem introduced by Bernheim and Whinston (1986); Rubinstein’s
model of alternating offer bargaining (Rubinstein 1982) hasbeendevelopedand
extended to ground a general theory of legislative decision-making and coalition
formation; Spence’s theory of costly signaling games (Spence 1974) and Crawford
and Sobel’s (1982) extension of this theory to costless (cheap-talk) signaling provide
the tools for a theory of legislative committees, delegation, informational lobbying,
debate, and so on. More recently, the growth of interest in behavioral economics,
experimental research, and so forth is beginning to appear in the political science
literature. Rather than sketch these and other applications of economic methods to
political science, this chapter attempts to articulate a broader (likely idiosyncratic)
view of positive political theory since the importation of formal rational choice theory
to politics. After all, political decision-making has at least as much of a claim to
being subject to rational choice as economic decision-making; political agents make
purposive decisions to promote their interests subject to constraints. It would be
odd, then, to discover that the methods of economics are of no value to the study
of politics.
References
Arrow, K.J.1951. Social Choice and Individual Values. New Haven, Conn.: Yale University
Press.
1963. Social Choice and Individual Values, 2nd edn. New Haven, Conn.: Yale University
Press.
¹⁵ The logic of this result is that the while, as Downs suggested, the relative number of voters voting
informatively declines as the electorate grows due to the diminishing likelihood of being pivotal, the
absolute number of voters voting informatively increases as the electorate grows at a faster rate, and it is
the latter that dominates the information aggregation.