Proportional representation (PR) refers to any type of electoral system under which subgroups of an electorate are reflected proportionately in the elected body. The concept applies mainly to political divisions among voters. The essence of such systems is that all votes cast – or almost all votes cast – contribute to the result and are effectively used to help elect someone. Under other election systems, a bare plurality or a scant majority are all that are used to elect candidates. Further, a PR system is one that produces mixed and balanced representation, reflecting how votes are cast.
Party-list proportional representation (list-PR) is a system of proportional representation based on preregistered political parties, with each party being allocated a certain number of seats roughly proportional to their share of the vote.
The single transferable vote (STV), sometimes mistakenly conflated with proportional ranked choice voting (P-RCV), is a multi-winner electoral system in which each voter casts a single vote in the form of a ranked-choice ballot. Voters have the option to rank candidates, and their vote may be transferred according to alternative preferences if their preferred candidate is eliminated or elected with surplus votes, so that their vote is used to elect someone they prefer over others in the running. STV aims to approach proportional representation based on votes cast in the district where it is used, so that each vote is worth about the same as another.
Single non-transferable vote or SNTV is an electoral system used to elect multiple winners. It is a generalization of first-past-the-post, applied to multi-member districts with each voter casting just one vote. Unlike FPTP, which is a single-winner system, in SNTV multiple winners are elected, typically in electoral districts; additionally, unlike FPTP, SNTV produces mixed representation and makes it unlikely for a single party to take all the seats in a city or a set area, which can happen under FPTP.
Elections in Sweden are held once every four years. At the highest level, all 349 members of Riksdag, the national parliament of Sweden, are elected in general elections. Elections to the 20 county councils and 290 municipal assemblies – all using almost the same electoral system – are held concurrently with the legislative elections on the second Sunday in September.
The additional-member system (AMS) or is a mixed electoral system under which most representatives are elected in single-member districts (SMDs), and a fixed number of other "additional members" are elected to make the seat distribution in the chamber more proportional to the way votes are cast for party lists. It is distinct from parallel voting in that the "additional member" seats are awarded to parties taking into account seats won in SMDs, which is not done under parallel voting.
Mixed-member proportional representation is a mixed electoral system which combines local winner-take-all elections with a compensatory tier of party list votes, which are used to allocate additional members in a way that aims to produce proportional representation overall. In typical MMP systems, voters get two votes: one to decide the representative for their single-seat constituency, and one for a political party. Some countries use single vote variants of MMP, although this article focuses primarily on dual vote versions of MMP.
In political science, parallelvoting or superposition refers to the use of two or more electoral systems to elect different members of a legislature. More precisely, an electoral system is a superposition if it is a mixture of at least two tiers, which do not interact with each other in any way; one part of a legislature is elected using one method, while another part is elected using a different method, with all voters participating in both. Thus, the final results can be found by calculating the results for each system separately based on the votes alone, then adding them together. A system is called fusion or majority bonus, another independent mixture of two system but without two tiers. Superposition is also not the same as "coexistence", which when different districts in the same election use different systems. Superposition, fusion and coexistence are distinct from dependent mixed electoral systems like compensatory (corrective) and conditional systems.
Open list describes any variant of party-list proportional representation where voters have at least some influence on the order in which a party's candidates are elected. This is as opposed to closed list, in which party lists are in a predetermined, fixed order by the time of the election and gives the general voter no influence at all on the position of the candidates placed on the party list.
An electoraldistrict, sometimes called a constituency, riding, or ward, is a subdivision of a larger state created to provide its population with representation in the larger state's legislature. That body, or the state's constitution or a body established for that purpose, determines each district's boundaries and whether each will be represented by a single member or multiple members. Generally, only voters (constituents) who reside within the district are permitted to vote in an election held there. District representatives may be elected by a first-past-the-post system, a proportional representative system, or another voting method. They may be selected by a direct election under universal suffrage, an indirect election, or another form of suffrage.
At a national level, Greece holds elections for its legislature, the Hellenic Parliament.
In the study of apportionment, the Harequota is the number of voters represented by each legislator under an idealized system of proportional representation, where every legislator represents an equal number of voters. The Hare quota is the total number of votes divided by the number of seats to be filled. The Hare quota was used in the original proposal for a single transferable vote system, and is still occasionally used, although it has since been largely supplanted by the Droop quota.
A single-member district or constituency is an electoral district represented by a single officeholder. It contrasts with a multi-member district, which is represented by multiple officeholders.
There are a number of complications and issues surrounding the application and use of single transferable vote proportional representation that form the basis of discussions between its advocates and detractors.
Block plurality voting is a winner-take-all method for multi-winner elections. Each voter may cast as many votes as the number of seats to be filled. The usual result when the candidates divide into parties is that the most popular party in the district sees its full slate of candidates elected.
Electoral districts go by different names depending on the country and the office being elected.
The German federal election system regulates the election of the members of the national parliament, called the Bundestag. According to the principles governing the elections laws, set down in Art. 38 of the German Basic Law, elections are to be universal, direct, free, equal, and secret. Furthermore, the German Basic Law stipulates that Bundestag elections are to take place every four years and that one can vote, and be elected, upon reaching the age of 18. All other stipulations for the federal elections are regulated by the Federal Electoral Act. Elections always take place on a Sunday. Mail votes are possible upon application.
Semi-proportional representation characterizes multi-winner electoral systems which allow representation of minorities, but are not intended to reflect the strength of the competing political forces in close proportion to the votes they receive. Semi-proportional voting systems are generally used as a compromise between complex and expensive but more-proportional systems and simple winner-take-all systems. Examples of semi-proportional systems include the single non-transferable vote, limited voting, and parallel voting.
An electoral or voting system is a set of rules that determine how elections and referendums are conducted and how their results are determined. Electoral systems are used in politics to elect 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, how votes translate into the election outcome, limits on campaign spending, and other factors that can affect the result. 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.
Mixed-member majoritarian representation (MMM) is type of a mixed electoral system combining winner-take-all and proportional methods, where the disproportional results of the winner-take-all part are dominant over the proportional component. Mixed member majoritarian systems are therefore categorized under semi-proportional representation, and are usually contrasted with mixed-member proportional representation (MMP) which aims to provide proportional representation compensation ("top-up") seats.
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