Importance that revêt the act to vote in a democratic system justifies that many theorists are leaning on the voting systems . To date, several voting systems in force or are proposed; they cause many Polémique S which take part in the intensification of the democracy.

The object of this article is to make an inventory of the voting systems in force or reflection and to specify the constraints of “a good” voting system.

The aspects of electoral Procedure (calculation, poll, etc) and of Electorate and eligibility are treated in addition.

A voting system can also concerned the weight allotted to each vote.

Characteristics of a good voting system

Theorem of impossibility

It is impossible to say that such or such voting system is system perfect, because some of characteristics, which makes that a system is good, are contradictory. If, for example, a candidate is extremely appreciated by the majority of the voters, but also extremely haï by the others; does that make of him the best or a worse candidate than that which would be moderately appreciated by all? The voting systems have each one a vision different from this type of problems.

Kenneth Arrow received the Prix of the Bank of Sweden in economic scenes in memory of Alfred Nobel in 1972 to have shown, in its thesis of 1951, impossibility of transforming individual preferences into collective choice without violating at least one of the following conditions:

  • the voting system must always succeed.
  • All the possibilities must be able to be carried out.
  • No dictatorship: the system should not take account of the choices of an individual with the detriment of the others.
  • If a voter improves the row of an option, that should never handicap it.
  • Ôter a candidate (other that one gaining) should not change the result of the vote.

In fact, all the various systems violate various ways these conditions. Many finds that the Méthode Condorcet remains sufficiently good, because she violates only in a minor way a criterion among the least important.

Some criteria to be observed

To organize an election, it is important to create conditions so that the vote is most democratic possible. These criteria to be respected are developed in the article electoral Procédure.

The various voting systems have certain advantages and certain disadvantages. To determine the voting system which corresponds best to the objective of the organizer, were specified Critères of voting systems. They make it possible to facilitate the choice of the organizer but there does not exist any voting system checking all the inventoried criteria.

Nonexhaustive inventory

See article: nominal Vote

The methods being the same ones, one will not distinguish between the bearing choices on people (election) and those which relate to decisions: the term of option will be used.

The majority of the voting systems belong to the one of the following categories, or are the result of the mixture of several of these categories.

For practical reasons, one will quote the polls with several turns, although these systems can be assimilated to combinations, within one only procedure, several distinct polls and sometimes according to different methods.

Lastly, it is necessary to point out that the vote is a system of particular Marché: the parties sell to the voters their options using promises, and the voters buy these options using an ad hoc currency, the “voice”; in fact the most sold options are retained. From there it is thus possible to imagine an infinity of alternatives, by changing very small little rules applicable to the currency used (the “voice”: data irrevocably or being able to be only lent for one limited time; exchangeable or not before the vote; at lifespan limited or on the contrary durable, fractionnable or not, etc), to the options which can be marketing, with the management of time (collection over one long period, as for a petition, or short), etc One can thus quote only part of the techniques of possible vote: most frequently actually used, and under consideration by the theory.

For memory, the most general system (the market where the “voice” is quite simply the ordinary currency) is evoked in the article Marché.

The representation proportional

Systems pre-proportional

Systems proportional

  • Vote of list to proportional the and its many alternatives (with the strongest average, the strongest remainder, by district, etc)
  • Vote of approval proportional
  • System of Hare or votes single transferable

Ways of voting majority

Uninominal systems

These various ways of voting allow only the candidate having gathered the most voice to be elected.
  • majority Poll with a turn (First-past-tea-post or Plurality)
  • alternative Vote (Urgent Runoff Voting)
  • majority Poll with two turns (Runoff voting): combination of two distinct vote, the first
  • Système with classification
    • Vote by approval (known as also vote by approval)
    • Méthode Condorcet
    • Méthode of Coombs
These voting systems per classification however present a fault concerning anonymity described in the article Electoral system to preferences multiple ordinates.

Plurinominaux polls

Such a system selects several (unbounded) options among a great number. It is the procedure which fixes the number of options selected, and if this number is fixed by advance or if it is one of the results of the vote.

Other systems

Polls aiming to the approval or the rejection of a predetermined option

This type of poll must, to function, be combined with a procedure to build and select the option to be subjected. Sometimes that makes it regard as less democratic, because of the constraints weighing on the choice.

Theorists of the voting systems

See too

External bonds

  • (held at the time of the first turn of the presidential election of 2007)
  • (information as regards elections, resulting from the project Administration and cost of the elections)
  • (blog)
  • (platform Web under license LPG)

  • (Resources comparing the methods of elections on the plan of their properties of resistance to strategies)

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