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 electoral threshold, or election threshold, is the minimum share of all the votes cast that a candidate or political party requires to achieve before they become entitled to representation or additional seats in a legislature. This limit can operate in various ways, e.g. in party-list proportional representation systems where an electoral threshold requires that a party must receive a specified minimum percentage of votes, either nationally or in a particular electoral district, to obtain seats in the legislature. In single transferable voting, the election threshold is called the quota and it is possible to pass it by use of first choice votes alone or by a combination of first choice votes and votes transferred from other candidates based on lower preferences. In mixed-member-proportional (MMP) systems the election threshold determines which parties are eligible for top-up seats in the legislative body.
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.
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 D'Hondt method reduces compared to ideal proportional representation somewhat the political fragmentation for smaller electoral district sizes, where it favors larger political parties over small parties.
The Webster method, also called the Sainte-Laguë method, is a highest averages apportionment method for allocating seats in a parliament among federal states, or among parties in a party-list proportional representation system. The Sainte-Laguë method shows a more equal seats-to-votes ratio for different sized parties among apportionment methods.
In mathematics, economics, and political science, the highest averages methods, also called divisor methods, are a class of apportionment algorithms for proportional representation. Divisor algorithms seek to fairly divide a legislature between agents. More generally, divisor methods are used to divide or round a whole number of objects being used to represent (non-whole) shares of a total.
The National Assembly of the Republic of Korea, often shortened to the National Assembly, is the unicameral national legislature of South Korea. Elections to the National Assembly are held every four years. The latest legislative elections was held on 10 April 2024. The National Assembly has 300 seats, with 253 constituency seats and 47 proportional representation seats; 30 of the PR seats are assigned an additional member system, while 17 PR seats use the parallel voting method.
The Imperiali quota or Imperiali pseudoquota is a formula used to calculate the number of votes needed to earn a seat, in single transferable vote or largest remainder elections. It is named after Belgian senator Pierre Imperiali.
The Gallagher index measures an electoral system's relative disproportionality between votes received and seats in a legislature. As such, it measures the difference between the percentage of votes each party gets and the percentage of seats each party gets in the resulting legislature, and it also measures this disproportionality from all parties collectively in any one given election. That collective disproportionality from the election is given a precise score, which can then be used in comparing various levels of proportionality among various elections from various electoral systems. The Gallagher index is a statistical analysis methodology utilised within political science, notably the branch of psephology.
The single transferable vote (STV) is a proportional representation voting system that elects multiple winners. It is one of several ways of choosing winners from ballots that rank candidates by preference. 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.
The Pedersen index is a measure of political volatility in party systems. It was described by Mogens Pedersen in a paper published in 1979 entitled The Dynamics of European Party Systems: Changing Patterns of Electoral Volatility.
Matthew Søberg Shugart is an American political scientist. He is a Distinguished Professor of political science at the University of California, Davis. He is also an Affiliated Professor at the University of Haifa. Shugart specializes in electoral systems, party systems, and the design of political institutions, primarily through empirical studies of political systems across large numbers of countries. Shugart is also an orchardist, and runs the Fruits and Votes blog on electoral systems and fruit growing.
In voting theory, the micromega rule holds that, when political parties choose electoral systems, "the large prefer the small and the small prefer the large". The term "micromega" references Micromégas, a tale by Voltaire in which dwarfs and giants dialogue.
Party-list representation in the House of Representatives of the Philippines refers to a system in which 20% of the House of Representatives is elected. While the House is predominantly elected by a plurality voting system, known as a first-past-the-post system, party-list representatives are elected by a type of party-list proportional representation. The 1987 Constitution of the Philippines created the party-list system. Originally, the party-list was open to underrepresented community sectors or groups, including labor, peasant, urban poor, indigenous cultural, women, youth, and other such sectors as may be defined by law. However, a 2013 Supreme Court decision clarified that the party-list is a system of proportional representation open to various kinds of groups and parties, and not an exercise exclusive to marginalized sectors. National parties or organizations and regional parties or organizations do not need to organize along sectoral lines and do not need to represent any marginalized and underrepresented sector.
The Loosemore–Hanby index measures disproportionality of electoral systems, how much the principle of one person, one vote is violated. It computes the absolute difference between votes cast and seats obtained using the formula:
Apportionment in the Hellenic Parliament refers to those provisions of the Greek electoral law relating to the distribution of Greece's 300 parliamentary seats to the parliamentary constituencies, as well as to the method of seat allocation in Greek legislative elections for the various political parties. The electoral law was codified for the first time through a 2012 Presidential Decree. Articles 1, 2, and 3 deal with how the parliamentary seats are allocated to the various constituencies, while articles 99 and 100 legislate the method of parliamentary apportionment for political parties in an election. In both cases, Greece uses the largest remainder method.
Grigorii V. Golosov, sometimes spelled as Grigory Golosov, is a Russian political scientist. He is a professor and the Head of Political Science Department at the European University at Saint Petersburg, Russia. He is notable as expert on political institutions and electoral systems, in particular, in application to Russia. His article "Electoral Systems and Party Formation in Russia" received a Lawrence Longley Award of the American Political Science Association for the best journal article on electoral systems and representation published in 2003.
The 2005 Devon County Council election was an election to Devon County Council which took place on 5 May 2005 as part of the 2005 United Kingdom local elections. 62 councillors were elected from various electoral divisions, which returned either one or two county councillors each by first-past-the-post voting for a four-year term of office. The electoral divisions had been redrawn since the last election in 2001. No elections were held in Plymouth and Torbay, which are unitary authorities outside the area covered by the County Council.
