Voting is a method for a group such as a meeting or an electorate to make a decision or express an opinion—often following discussions, debates, or election campaigns. Democracies elect holders of high office by voting. A voting system or electoral system is a method by which voters make a choice between options, often in an election or on a policy referendum.
A voting system enforces rules to ensure valid voting, and how votes are counted and aggregated to yield a final result. Common voting systems are majority rule, proportional representation or plurality voting with a number of variations and methods such as first-past-the-post or preferential voting. The study of formally defined voting systems is called social choice theory or voting theory, a subfield of political science, economics, or mathematics.
With majority rule, those who are unfamiliar with voting theory are often surprised that another voting system exists, or that disagreements may exist over the definition of what it means to be supported by a majority. Depending on the meaning chosen, the common “majority rule” systems can produce results that the majority does not support. If every election had only two choices, the winner would be determined using majority rule alone. However, when there are three or more options, there may not be a single option that is most liked or most disliked by a majority. A simple choice does not allow voters to express the ordering or the intensity of their feeling. Different voting systems may give very different results, particularly in cases where there is no clear majority preference.
In a democracy, a government is chosen by voting in an election: a way for an electorate to elect, i.e. choose, among several candidates for rule. In a representative democracy voting is the method by which the electorate appoints its representatives in its government. In a direct democracy, voting is the method by which the electorate directly make decisions, turn bills into laws, etc.
A vote is a formal expression of an individual’s choice in voting, for or against some motion (for example, a proposed resolution), for or against some ballot question, for a certain candidate, a selection of candidates, or a political party. A secret ballot has come to be the practice to prevent voters from being intimidated and to protect their political privacy.
Voting usually takes place at a polling station; it is voluntary in some countries, compulsory in others, such as Australia.
Different voting systems use different types of votes. A “Plurality voting system” does not require the winner to achieve a vote majority, or more than fifty percent of the total votes cast. In a voting system that uses a single vote per race, when more than two candidates run, the winner may commonly have less than fifty percent of the vote.
A side effect of a single vote per race is vote splitting, which tends to elect candidates that do not support centrism, and tends to produce a two-party system. An alternative to a single-vote system is approval voting.
To understand why a single vote per race tends to favor less centric candidates, consider a simple lab experiment where students in a class vote for their favorite marble. If five marbles are assigned names and are placed “up for election,” and if three of them are green, one is red, and one is blue, then a green marble will rarely win the election. The reason is that the three green marbles will split the votes of those who prefer green. In fact, in this analogy, the only way that a green marble is likely to win is if more than sixty percent of the voters prefer green. If the same percentage of people prefer green as those who prefer red and blue, that is to say if 33 percent of the voters prefer green, 33 percent prefer blue, and 33 percent prefer red, then each green marble will only get eleven percent of the vote, while the red and blue marbles will each get 33 percent, putting the green marbles at a serious disadvantage. If the experiment is repeated with other colors, the color that is in the majority will still rarely win. In other words, from a purely mathematical perspective, a single-vote system tends to favor a winner that is different from the majority. If the experiment is repeated using approval voting, where voters are encouraged to vote for as many candidates as they approve of, then the winner is much more likely to be any one of the five marbles, because people who prefer green will be able to vote for every one of the green marbles.
A development on the ‘single vote’ system is to have two-round elections, or repeat first-past-the-post. The winner must receive a majority, which is more than half. If subsequent votes must be used, often a candidate, the one with the fewest votes or anyone who wants to move their support to another candidate, is removed from the ballot.
An alternative to the Two-round voting system is the single round instant-runoff voting system (Also referred to as Alternative vote or Preferential voting) as used in some elections in Australia, Ireland and the USA. Voters rank each candidate in order of preference (1,2,3 etc.). Votes are distributed to each candidate according to the preferences allocated. If no single candidate has 50% or more votes then the candidate with the least votes is excluded and their votes redistributed according to the voters nominated order of preference. The process repeating itself until a candidate has 50% or more votes. The system is designed to produce the same result as an exhaustive ballot but using only a single round of voting.
In a voting system that uses a multiple vote, the voter can vote for any subset of the alternatives. So, a voter might vote for Alice, Bob, and Charlie, rejecting Daniel and Emily. Approval voting uses such multiple votes.
In a voting system that uses a ranked vote, the voter has to rank the alternatives in order of preference. For example, they might vote for Bob in first place, then Emily, then Alice, then Daniel, and finally Charlie. Ranked voting systems, such as those famously used in Australia, use a ranked vote.
In a voting system that uses a scored vote (or range vote), the voter gives each alternative a number between one and ten (the upper and lower bounds may vary). See cardinal voting systems.
Some “multiple-winner” systems may have a single vote or one vote per elector per available position. In such a case the elector could vote for Bob and Charlie on a ballot with two votes. These types of systems can use ranked or unranked voting, and are often used for at-large positions such as on some city councils.
A voting system specifies the form of the ballot, the set of allowable votes, and the tallying method, an algorithm for determining the outcome. This outcome may be a single winner, or may involve multiple winners such as in the election of a legislative body. The voting system may also specify how voting power is distributed among the voters, and how voters are divided into subgroups (constituencies) whose votes are counted independently.
The real-world implementation of an election is generally not considered part of the voting system. For example, though a voting system specifies the ballot abstractly, it does not specify whether the actual physical ballot takes the form of a piece of paper, a punch card, or a computer display. A voting system also does not specify whether or how votes are kept secret, how to verify that votes are counted accurately, or who is allowed to vote. These are aspects of the broader topic of elections and election systems.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s