Electoral system

  • map showing the electoral systems used to elect candidates to the lower house of national legislatures, as of 2019.
    majoritarian system
      first-past-the-post voting
      two-round system
      instant-runoff voting
      plurality-at-large voting
      general ticket
    semi-proportional system
      single non-transferable vote
      cumulative voting
      binomial system
    proportional system
      party-list proportional representation
      single transferable voting
    mixed system
      majority bonus system
        mixed-member proportional representation
            parallel voting
    other
      borda count

      no direct election
      no information

    an electoral system or voting system is a set of rules that determine how elections and referendums are conducted and how their results are determined. political electoral systems are organized by governments, while non-political elections may take place in business, non-profit organisations and informal organisations. these rules govern all aspects of the voting process: when elections occur, who is allowed to vote, who can stand as a candidate, how ballots are marked and cast, how the ballots are counted (electoral method), limits on campaign spending, and other factors that can affect the outcome. political electoral systems are defined by constitutions and electoral laws, are typically conducted by election commissions, and can use multiple types of elections for different offices.

    some electoral systems elect a single winner to a unique position, such as prime minister, president or governor, while others elect multiple winners, such as members of parliament or boards of directors. there are many variations in electoral systems, but the most common systems are first-past-the-post voting, the two-round (runoff) system, proportional representation and ranked voting. some electoral systems, such as mixed systems, attempt to combine the benefits of non-proportional and proportional systems.

    the study of formally defined electoral methods is called social choice theory or voting theory, and this study can take place within the field of political science, economics, or mathematics, and specifically within the subfields of game theory and mechanism design. impossibility proofs such as arrow's impossibility theorem demonstrate that when voters have three or more alternatives, it is not possible to design a ranked voting electoral system that reflects the preferences of individuals in a global preference of the community, present in countries with proportional representation and plurality voting.

  • types of electoral systems
  • rules and regulations
  • history
  • comparison of electoral systems
  • see also
  • references
  • external links

Map showing the electoral systems used to elect candidates to the lower house of national legislatures, as of 2019.
Majoritarian system
Semi-proportional system
Proportional system
Mixed system
  Majority bonus system
    Mixed-member proportional representation
        Parallel voting
Other

  No direct election
  No information

An electoral system or voting system is a set of rules that determine how elections and referendums are conducted and how their results are determined. Political electoral systems are organized by governments, while non-political elections may take place in business, non-profit organisations and informal organisations. These rules govern all aspects of the voting process: when elections occur, who is allowed to vote, who can stand as a candidate, how ballots are marked and cast, how the ballots are counted (electoral method), limits on campaign spending, and other factors that can affect the outcome. Political electoral systems are defined by constitutions and electoral laws, are typically conducted by election commissions, and can use multiple types of elections for different offices.

Some electoral systems elect a single winner to a unique position, such as prime minister, president or governor, while others elect multiple winners, such as members of parliament or boards of directors. There are many variations in electoral systems, but the most common systems are first-past-the-post voting, the two-round (runoff) system, proportional representation and ranked voting. Some electoral systems, such as mixed systems, attempt to combine the benefits of non-proportional and proportional systems.

The study of formally defined electoral methods is called social choice theory or voting theory, and this study can take place within the field of political science, economics, or mathematics, and specifically within the subfields of game theory and mechanism design. Impossibility proofs such as Arrow's impossibility theorem demonstrate that when voters have three or more alternatives, it is not possible to design a ranked voting electoral system that reflects the preferences of individuals in a global preference of the community, present in countries with proportional representation and plurality voting.