Calculus of voting

Last updated

Calculus of voting refers to any mathematical model which predicts voting behaviour by an electorate, including such features as participation rate. A calculus of voting represents a hypothesized decision-making process.

These models are used in political science in an attempt to capture the relative importance of various factors influencing an elector to vote (or not vote) in a particular way.

Example

One such model was proposed by Anthony Downs (1957) and is adapted by William H. Riker and Peter Ordeshook, in “A Theory of the Calculus of Voting” (Riker and Ordeshook 1968)

V = pBC + D

where

V = the proxy for the probability that the voter will turn out
p = probability of vote “mattering”
B = “utility” benefit of voting--differential benefit of one candidate winning over the other
C = costs of voting (time/effort spent)
D = citizen duty, goodwill feeling, psychological and civic benefit of voting (this term is not included in Downs's original model)

A political science model based on rational choice used to explain why citizens do or do not vote.

The alternative equation is

V = pB + D > C

Where for voting to occur the (P)robability the vote will matter "times" the (B)enefit of one candidate winning over another combined with the feeling of civic (D)uty, must be greater than the (C)ost of voting

Related Research Articles

<span class="mw-page-title-main">Approval voting</span> Single-winner electoral system

Approval voting is an electoral system in which voters can select any number of candidates instead of selecting only one.

Rational choice theory refers to a set of guidelines that help understand economic and social behaviour. The theory originated in the eighteenth century and can be traced back to the political economist and philosopher Adam Smith. The theory postulates that an individual will perform a cost–benefit analysis to determine whether an option is right for them. It also suggests that an individual's self-driven rational actions will help better the overall economy. Rational choice theory looks at three concepts: rational actors, self interest and the invisible hand.

In social choice theory, a Condorcet paradox is a situation where majority rule behaves in a way that is self-contradictory. In such a situation, every possible choice is rejected by the electorate in favor of another, because there is always some other outcome that a majority of voters consider to be better.

In political science, Duverger's law holds that in political systems with only one winner, two main parties tend to emerge with minor parties typically splitting votes away from the most similar major party. In contrast, systems with proportional representation usually have more representation of minor parties in government.

William Harrison Riker was an American political scientist who is prominent for applying game theory and mathematics to political science. He helped to establish University of Rochester as a center of behavioral revolution in political science.

<span class="mw-page-title-main">Stochastic process</span> Collection of random variables

In probability theory and related fields, a stochastic or random process is a mathematical object usually defined as a sequence of random variables in a probability space, where the index of the sequence often has the interpretation of time. Stochastic processes are widely used as mathematical models of systems and phenomena that appear to vary in a random manner. Examples include the growth of a bacterial population, an electrical current fluctuating due to thermal noise, or the movement of a gas molecule. Stochastic processes have applications in many disciplines such as biology, chemistry, ecology, neuroscience, physics, image processing, signal processing, control theory, information theory, computer science, and telecommunications. Furthermore, seemingly random changes in financial markets have motivated the extensive use of stochastic processes in finance.

Public choice, or public choice theory, is "the use of economic tools to deal with traditional problems of political science." Its content includes the study of political behavior. In political science, it is the subset of positive political theory that studies self-interested agents and their interactions, which can be represented in a number of ways—using standard constrained utility maximization, game theory, or decision theory. It is the origin and intellectual foundation of contemporary work in political economy.

Independence of irrelevant alternatives (IIA), also known as binary independence, the independence axiom, is an axiom of decision theory and economics describing a necessary condition for rational behavior. The axiom says that a choice between and should not depend on the quality of a third, unrelated outcome .

Rational ignorance is refraining from acquiring knowledge when the supposed cost of educating oneself on an issue exceeds the expected potential benefit that the knowledge would provide.

<span class="mw-page-title-main">Voter turnout</span> Percentage of a countrys eligible voters who actually vote within elections

In political science, voter turnout is the participation rate of a given election. This is typically either the percentage of registered voters, eligible voters, or all voting-age people. According to Stanford University political scientists Adam Bonica and Michael McFaul, there is a consensus among political scientists that "democracies perform better when more people vote."

In political science and social choice theory, the median voter theorem states that if voters and candidates are distributed along a one-dimensional spectrum and voters have single peaked preferences, any voting method satisfying the Condorcet criterion will elect the candidate preferred by the median voter.

Anthony Downs was an American economist specializing in public policy and public administration. His research focuses included political choice theory, rent control, affordable housing, and transportation economics. He wrote a number of books including, An Economic Theory of Democracy (1957) and Inside Bureaucracy (1967), which have been major influences on the public choice school of political economy. In Downs's Law of Peak-Hour Traffic Congestion (1962), he predicted that expanding expressways could not reduce traffic congestion, since demand would increase as well, and that reducing speeds increases capacity.

Positive political theory (PPT), explanatory political theory, or formal theory is the study of politics using formal methods such as social choice theory, game theory, and statistical analysis. In particular, social choice theoretic methods are often used to describe and (axiomatically) analyze the performance of rules or institutions. The outcomes of the rules or institutions described are then analyzed by game theory, where the individuals/parties/nations involved in a given interaction are modeled as rational agents playing a game, guided by self-interest. Based on this assumption, the outcome of the interactions can be predicted as an equilibrium of the game.

<span class="mw-page-title-main">William Ernest Johnson</span> British philosopher, logician and economic theorist

William Ernest Johnson, FBA, usually cited as W. E. Johnson, was a British philosopher, logician and economic theorist. He is mainly remembered for his 3 volume Logic which introduced the concept of exchangeability.

Peter Carl Ordeshook is an American political scientist. He is the Mary Stillman Harkness Professor of Political Science at the California Institute of Technology in Pasadena, California.

The Theory of Political Coalitions is an academic book on positive political theory written by the American political scientist William H. Riker and published in 1962. It uses game theory to formalize political theory. In it, Riker deduces the size principle. On its postulates, politicians are proved to form winning, minimal-size coalitions. The work runs contrary to a previous theory by Anthony Downs that they try to maximize their respective votes. Riker supposes that attracting more votes requires resources and that politicians run to win. A rational politician tries to form a coalition that is as large as necessary to win but not larger.

<span class="mw-page-title-main">Paradox of voting</span> Aspect of politics

The paradox of voting, also called Downs' paradox, is that for a rational, self-interested voter, the costs of voting will normally exceed the expected benefits. Because the chance of exercising the pivotal vote is minuscule compared to any realistic estimate of the private individual benefits of the different possible outcomes, the expected benefits of voting are less than the costs.

The altruism theory of voting is a model of voter behavior which states that if citizens in a democracy have "social" preferences for the welfare of others, the extremely low probability of a single vote determining an election will be outweighed by the large cumulative benefits society will receive from the voter's preferred policy being enacted, such that it is rational for an “altruistic” citizen, who receives utility from helping others, to vote. Altruistic voting has been compared to purchasing a lottery ticket, in which the probability of winning is extremely low but the payoff is large enough that the expected benefit outweighs the cost.


A major branch of social choice theory is devoted to the comparison of electoral systems, otherwise known as social choice functions. Viewed from the perspective of political science, electoral systems are rules for conducting elections and determining winners from the ballots cast. From the perspective of economics, mathematics, and philosophy, a social choice function is a mathematical function that determines how a society should make choices, given a collection of individual preferences.

Heresthetic is an approach to understanding how political actors manipulate the decision-making process so they can win. Heresthetic is a positive political theory, including aspects of game theory, public choice theory, rational choice theory, and social choice theory to political science. Political scientist William H. Riker is considered the creator and one of the most prominent supports of theory.

References