Proportional representation (PR) refers to a 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 – not just a bare plurality or (exclusively) the majority – and that the system produces mixed, balanced representation reflecting how votes are cast.
Party-list proportional representation (list-PR) is a subset of proportional representation electoral systems in which multiple candidates are elected through their position on an electoral list. They can also be used as part of mixed-member electoral systems.
The single transferable vote (STV), sometimes known as 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 alternate 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.
The Droop quota is the quota most commonly used in elections held under the single transferable vote (STV) system. It is also sometimes used in elections held under the largest remainder method of party-list proportional representation. Any candidate that receives quota is declared elected. Under some STV systems, especially those of the full-preferential voting variant, all the winners receive the quota, but in others, of the optional-preferential voting or semi-optional preferential voting variants, it is common for as many as three winners in a district to be elected with less than quota.
Mixed-member proportional representation is a mixed electoral system in which votes are cast for both local elections and also for overall party vote tallies, which are used to allocate additional members to produce or deepen overall proportional representation.
The D'Hondt method, also called the Jefferson method or the greatest divisors method, is an apportionment method for allocating seats in parliaments among federal states, or in proportional representation among political parties. It belongs to the class of highest-averages methods.
The Webster method, also called the Sainte-Laguë method, is an apportionment method for allocating seats in a parliament among federal states, or among parties in a party-list proportional representation system.
A highest-averages method, also called a divisor method, is a class of methods for allocating seats in a parliament among agents such as political parties or federal states. A divisor method is an iterative method: at each iteration, the number of votes of each party is divided by its divisor, which is a function of the number of seats currently allocated to that party. The next seat is allocated to the party whose resulting ratio is largest.
The largest remainder method is one way of allocating seats proportionally for representative assemblies with party list voting systems. It contrasts with various highest averages methods.
The Hare quota is a formula used under some forms of proportional representation. In these voting systems the quota is the number of votes that guarantees a candidate, or a party in some cases, captures a seat. The Hare quota is the total number of votes divided by the number of seats to be filled. This is the simplest quota, but the Droop quota is mostly used currently.
There are two types of elections in Andorra: parliamentary elections and local elections. The 28 members of the General Council of the Valleys are elected in parliamentary elections for a maximum term of four years. In the local elections, the council members of the seven parishes of Andorra are elected for a four-year term.
Aruba elects a legislature on the national level. The Estates (Staten) have 21 members, elected for a four-year term by Open list Party-list proportional representation. Seats are distributed between parties that have gained at least one full quota using the Hagenbach-Bischoff system. Before obtaining the status as land (English: country in the Kingdom of the Netherlands, Aruba participated in elections for its Island Council and for the Aruba constituency of the parliament of the Netherlands Antilles.
The Hagenbach-Bischoff quota is a formula used in some voting systems based on proportional representation (PR). It is used in some elections held under the largest remainder method of party-list proportional representation as well as in a variant of the D'Hondt method known as the Hagenbach-Bischoff system. The Hagenbach-Bischoff quota is named for its inventor, Swiss professor of physics and mathematics Eduard Hagenbach-Bischoff (1833–1910).
The single transferable vote (STV) is a proportional representation voting system that elects multiple winners based on ranked voting. Under STV, an elector's vote is initially allocated to their most-preferred candidate. Candidates are elected (winners) if their vote tally reaches quota. After this 1st Count, if seats still remain open, surplus votes are transferred from winners to remaining candidates (hopefuls) according to the surplus ballots' next usable back-up preference. if no surplus votes have to be transferred, then the least-popular candidate is eliminated so the vote has chance to be placed on a candidate who can use it.
The Huntington–Hill method is a method for proportional allocation of the seats in a representative assembly by minimizing the percentage differences in the number of constituents represented by each seat. Edward Huntington formulated this approach, building on the earlier work of Joseph Adna Hill, and called it the method of equal proportions. Since 1941, this method has been used to apportion the 435 seats in the United States House of Representatives following the completion of each decennial census.
Parliamentary elections were held in Iceland on 25 April 1987. The Independence Party remained the largest party in the Lower House of the Althing, winning 12 of the 42 seats.
The 2008 Lower Austrian state election was held on 9 March 2008 to elect the members of the Landtag of Lower Austria.
The 2010 Burgenland state election was held on 30 May 2010 to elect the members of the 20th Landtag of Burgenland.
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. 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.
National remnant is a method used to allocate seats in a party-list proportional representation electoral system that has electoral districts. The system uses a Largest remainder method to determine some of the seats in each electoral district. However, after the integer part of the seats in each district is allocated to the parties, the seats left unallocated will then be allocated not in each electoral district in isolation, but in a larger division, such as nationwide or in large separate regions that each encompass multiple electoral districts.
