Proportional representation

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Proportional representation (PR), sometimes referred to as full representation, is a class of voting system aimed at securing a close match between the percentage of votes that groups of candidates obtain in elections, and the percentage of seats they receive (e.g., in legislative assemblies).

PR is often contrasted to plurality voting systems, such as those commonly used in the United States and (much of) the United Kingdom, where disproportional seat distribution results from the division of voters into multiple electoral districts, especially "winner takes all" plurality ("first-past-the-post" or FPTP) districts.

1 Methods of proportional representation
2 History
3 Partial proportionality
4 Center based proportional and multi-party systems
5 List of countries using proportional representation
6 Further reading
7 See also
8 Notes
9 External links

Methods of proportional representation

Proportional representation allows all voters a degree of influence on the political process. Proportional systems typically use political parties as the measure of representation. For example, a party that receives 15% of the votes under such a system receives 15% of the seats.^[1] By contrast, the established parties in current US and UK elections can, and most often do, win control of the parliament with support from as little as 20-25% of eligible voters, at the cost of smaller parties.^[2]

Different methods of proportional representation achieve either greater proportionality or a more determinate outcome.^[3]

Party-list proportional representation is one approach, in which the above-mentioned groups correspond directly with candidate lists from political parties. The open list form allows the voter to influence the election of individual candidates within a party list. The closed list approach does not. Another variation is the single transferable vote (STV), which does not depend on political parties (and where the "measure of grouping" is entirely left up to the voters.) Elections for the Australian Senate use what is referred to as above-the-line voting where candidates for each party are grouped on the ballot, allowing the voter for the group or for a candidate.

Other variations include single non-transferable vote (SNTV), cumulative voting and limited bloc voting (LBV), all of which offer a form of semi-proportional representation (SPR).

The emphasis on political parties may reduce PR's effectiveness. Political parties' influence is declining in countries such as the U.S., which in 2004 saw 24% of voters declaring themselves to be independent. In such polities, an alternative such as #loser delegation can achieve full representation in a different way.

Party list system in a multi-member constituency

The parties each list their candidates according to that party's determination of priorities. In closed list systems, voters vote for a list, not a candidate. Each party is allocated seats in proportion to the number of votes it receives, using the party-determined ranking order. In an open list, voters may vote, depending on the model, for one person, or for two, or indicate their order of preference within the list.

This system is used in many countries, including Finland (open list), Sweden (open list), Israel (where the whole country is one closed list constituency), Brazil (open list), the Netherlands (open list), South Africa (closed list), Democratic Republic of the Congo (open list) and for elections to the European Parliament in most European Union countries (mostly open lists, with the exception of Ireland and Northern Ireland using Single transferable vote and the remainder of the United Kingdom using closed lists).

Additional-member system, mixed-member system

Main articles: Additional Member Systems - mixed member proportional representation and parallel voting; alternative vote and alternative vote top-up

Mixed election systems combine a proportional system and a single seat district system, attempting to achieve some of the positive features of each. Mixed systems are often helpful in countries with large populations, since they balance local and national concerns. They are used in nations with diverse geographic, social, cultural and economic issues, including Bolivia, Germany, Lesotho, Mexico and the United Kingdom.

Such systems, or variations of them, are used in the UK - Greater London Authority, Germany, Lesotho, Mexico, Bolivia, New Zealand, the Scottish Parliament and the Welsh Assembly. Italy has changed between sub-systems.

Single transferable vote in a multi-member constituency

Main article: Single Transferable Vote

This system uses preferential voting.

Each constituency elects two or more representatives per electorate. Consequently the constituency is proportionally larger than single member constituencies that produce the same number of representatives. Parties tend to offer as many candidates as they optimistically could expect to win: major parties nominate more than minor parties. Voters allocate "votes" to their preferred ranking for some or all candidates. A successful candidate must achieve a quota, which is the number of votes cast divided by the number of candidates to be elected plus one; i.e. in a nine member constituency the quota would be (the number of votes divided by 10) +1. Only in a few cases is this achieved at the first count. For the second count, if a candidate wins election her/his surplus vote (in excess of the quota) is transferred to the voters' second choices; otherwise, the least popular candidate is eliminated and those votes are redistributed according to the second preference shown on them. If more than one candidate cannot get enough votes after the transfer of votes of the least popular candidate, that candidate is also eliminated (as they would be eliminated on the next round anyway.)

The process repeats until all seats are filled either when the required number of candidates achieve the quota or until the number of remaining candidates matches the number of remaining seats. Although the counting process is complicated, voting is clear and most voters get at least one of their preferences elected.

All deputies are answerable directly to their local constituents. Some political scientists argue that STV is more properly classified as 'semi-proportional' as there is no assurance of a proportional result at a national level. Indeed, many advocates of STV argue that preventing nationwide proportionality is one of the primary goals of the system, to avoid the perceived risks of a fragmented legislature.

This system is used in Australia (Senate, Tasmanian and Australian Capital Territory Houses of Assembly and the Legislative Councils in New South Wales, South Australia, Western Australia and Victoria), the Republic of Ireland, Northern Ireland (assembly and local government elections), Malta, local government elections in Scotland, Wales and selected (optional) local governments in New Zealand.

Loser delegation in a single-member constituency

"Loser delegation" voting can produce still greater representation in legislatures. This system allows losing candidates to delegate the votes they receive to the winning candidate in their own or in another district without regard to party. Delegated votes don't affect who enters the legislature, but they do affect subsequent legislative votes. Each representative's legislative votes are weighted by the sum of the direct and delegated votes they received. Delegated voting can be combined with first-past-the-post, instant-runoff, or other counting rules that determine the winning candidate.

For example, consider a district where Sarah receives 45% of the votes, while Barack takes 40%, leaving Joe with the remaining 15%. Under traditional first-past-the-post rules, Sarah wins, leaving 55% of the voters without representation. In instant run-off, if 80% of Joe's voters picked Barack as their second choice, he would win in the second round, with 52% of the final total to Sarah's 48%, bringing second-choice representation to 7% of the voters, while leaving Sarah's voters without a voice.

Under loser delegation in the instant-runoff case, Barack joins the legislature, while Sarah can sign her votes over to Mitt, who won with 56% in a nearby district. Now those who voted for Sarah have about as much voice in legislation (via Mitt) as Barack's voters; nobody is left unrepresented. Barack effectively casts 52 votes, Mitt casts 56 + 48 or 101, and also-moderate Blanche casts 58 (her winning percentage in a third district.) Of course, the losers in Mitt and Blanche's districts also get to delegate their votes, so Barack could conceivably end up casting 52 + 44 + 42 or 138 votes.

However, combining proxy with first-past-the-post may be a better choice because that way Joe can choose to give his votes to Blanche instead of seeing them handed to Barack following the runoff. Now Sarah casts 45 as her district's representative, Barack delegates his 40 to Nancy to add to her 70, Mitt stays at 56, and Blanche casts 58 + 15 or 73.

History

The schoolmaster Thomas Wright Hill is credited as inventor of the single transferable vote, whose use he described in 1821 for application in elections at his school. The method, which guarantees proportional representation, was introduced in 1840 by his son Rowland Hill into the public election for the Adelaide City Council. Unlike several later systems, this did not allow for party-list proportional representation.

Single Transferable Vote was first used in Denmark in 1857, making STV the oldest PR system, but the system used there never really spread. STV was re-invented (apparently independently) in the UK, but the British parliament rejected it.

A party-list proportional representation system was first devised and described in 1878 by Victor D'Hondt of Belgium. The procedure, known as the D'Hondt method, is still widely used. Victor Considérant, a utopian socialist, devised a similar system in an 1892 book. Some Swiss cantons (beginning with Ticino in 1890) preceded Belgium which was the first to adopt list-PR in 1900 for its national parliament. Many European countries adopted similar systems during or after World War I.

STV was used in Tasmania in 1907. In the last Irish elections to the UK Parliament in 1919, STV was used in the University of Dublin constituency; two Independent Unionists were elected. STV has been in use since Irish independence. A mainly centrist party, Fianna Fáil, typically receives 30%-50% of the vote while opposition parties, traditionally the centre-right Fine Gael and the centre-left Labour Party, are comparatively weak. This has led to a series of coalition governments; there has not been a single-party government since 1989.

PR is used by more nations than the plurality voting system, and it dominates Europe, including Germany, most of northern and eastern Europe, and for European Parliament elections. France adopted PR at the end of World War II, discarding it in 1958. In 1986 it was used for parliament elections.

While FPTP is commonly found in countries based on the British parliamentary system, and in Westminster elections in the United Kingdom, the Scottish Parliament and the Welsh National Assembly use a form of PR known as the mixed member system, after New Zealand adopted it in 1993. Five Canadian provinces—British Columbia, Ontario, Quebec, Prince Edward Island and New Brunswick— are debating whether to abolish FPTP.

PR has some history in the United States. Many cities, including New York City, once used it to break up the Democratic Party city councils monopolies on elective office. Cincinnati, Ohio, adopted PR in 1925 to get rid of a Republican Party party machine, but the Republicans returned the city to FPTP in 1957. From 1870 to 1980, Illinois used a semi-proportional cumulative voting system to elect its State House of Representatives. Each district across the state elected both Republicans and Democrats year-after-year. Cambridge, Massachusetts and Peoria, Illinois continue to use PR. San Francisco had city-wide elections where people would cast votes for five or six candidates simultaneously, delivering some of the benefits of proportional representation.

In his essay, Overcoming Practical Difficulties in Creating a World Parliamentary Assembly, Joseph E. Schwartzberg proposes the use of proportional representation in the United Nations Parliamentary Assembly in order to prevent, for instance, lower castes of Indians from being excluded.^[4]

Partial proportionality

Some nations with proportional elections, like Israel and the Netherlands, have one electoral district only: the entire nation, and the entire pie is cut up according to the entire outcome. Most nations have district systems in place where more than one person is elected per district. The constituency or district magnitude (DM) of a system is therefore measured by the number of seats per constituency. The greater the number of seats in a constituency, the more proportional the outcome will be. PR applied to a single-member district (SMD) is by necessity majoritarian. If the constituency is in a jurisdiction using list PR in its multimember districts (MMDs) the winning candidate simply needs a plurality, otherwise called a simple or relative majority, of the vote to win, so that the election in the SMD is by first-past-the-post. If the constituency is in a jurisdiction using PR-STV in its MMDs, an absolute majority of 50% plus 1 will likely be the minimum required for victory (depending on which quota is used) so that the election in the SMD is by the alternative vote. Four elected officials per district delivers a threshold of 20% (1/M+1) to gain a single seat. However, constituency borders can still be gerrymandered to reduce proportionality. This may be achieved by creating "majority-minority" constituencies - constituencies in which the majority is formed by a group of voters that are in the minority at a higher level. Proportional representation with the entire nation electing the single body cannot be gerrymandered.

Multimember districts do not necessarily ensure that an electoral system will be proportional. The bloc vote can result in "super-majoritarian" results in which geographical variations can create majority-minority districts that become subsumed into the larger districts. Also, a party that does not run enough people to fill all the seats it wins may be given those unfilled seats. This is termed an underhang.

Some nations, with either exclusively proportional representation or—as is the case with Germany—additional member systems, require a party list to achieve an election threshold—a set minimum percentage of votes to receive any seats. Typically, this lower limit is between two and five percent of the number of votes cast. Parties who do not reach that support are not represented in parliament, making majorities, coalitions and thus governments easier to achieve. Proponents of election thresholds argue that they discourage fragmentation, disproportionate power, or extremist parties. Opponents of thresholds argue that they unfairly redirect support from minor parties, giving parties which cross the threshold disproportionate numbers of seats and creating the possibility that a party or coalition will assume control of the legislature without gaining a majority of votes.

The most common way of measuring proportionality is the Gallagher Index.

Center based proportional and multi-party systems

Election systems based on proportional representation tend to favor a multi-party result which demands a coalition to form a government supported by a majority of the voters or elected candidates. If the election system as well as the mechanisms for forming a governing coalition also tend to support the existence of a centrist party, the resulting over-all system is often defined as a "center-based proportional representation multi-party system". Election systems which tend to result in so-called two-block (many parties forming coalitions, blocks, but with no party, or "block", in the "center") systems are not seen as "center-based" but multi-party variations of two-party (two-block) systems.

The undesirable "extreme" of a "Center Based" system (like in Condorcet method) might be seen as a party system where the "center" has an unproportional and undesirable strong position in the formation of any governing coalition.

List of countries using proportional representation

This is a list of countries using proportional representation at national level.

Country	Type
Algeria	Party list
Angola	Party list
Australia	For Senate only, Single Transferable Vote
Austria	Party list
Argentina	Party list
Aruba	Party list
Belgium	Party list
Bolivia	Mixed Member Majoritarian
Brazil	Party list
Bulgaria	Party list
Burkina Faso	Party list
Burundi	Party list
Cambodia	Party list
Cape Verde	Party list
Colombia	Party list
Costa Rica	Party list
Croatia	Party list
Cyprus	Party list
Czech Republic	Party list
Democratic Republic of the Congo	Mixed member proportional
Denmark	Party list
Dominican Republic	Party list
Equatorial Guinea	Party list
Estonia	Party list
Finland	Party list
Germany	Mixed member proportional
Greece	Party list (with plurality bonus)
Guinea-Bissau	Party list
Guyana	Party list
Hungary	Mixed Member Majoritarian
Iceland	Party list
India	For Upper House (Rajya Sabha) only, Single Transferable Vote by State Legislatures
Indonesia	Party list
Iraq	Party list
Ireland	Single Transferable Vote
Israel	Party list
Italy	Party list (with plurality bonus for coalitions)
Japan	Mixed Member Majoritarian
Latvia	Party list
Lesotho	Mixed Member Majoritarian
Liberia	Party list
Liechtenstein	Party list
Luxembourg	Party list
Malta	Single Transferable Vote
Mexico	Mixed Member Majoritarian
Moldova	Party list
New Zealand	Mixed Member Proportional
Namibia	Party list
Netherlands	Party list
Netherlands Antilles	Party list
New Caledonia	Party list
Nicaragua	Party list
Northern Ireland	Single Transferable Vote (for regional assembly only)
Norway	Party list
Paraguay	Party list
Peru	Party list
Poland	Party list
Portugal	Party list
Romania	Party list
Russia	Party list
San Marino	Party list
Sao Tome and Principe	Party list
Scotland	Additional Member System (for national assembly only)
Slovakia	Party list
Slovenia	Party list
South Africa	Party list
South Korea	Party list
Spain	Party list
Sri Lanka	Party list
Suriname	Party list
Sweden	Party list
Switzerland	Party list
Taiwan	Mixed Member Majoritarian
Thailand	Mixed Member Majoritarian
Turkey	Party list
Ukraine	Party list
Uruguay	Party list
Venezuela	Party list
Wales	Additional Member System (for national assembly only)
Wallis and Futuna	Party list