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In political science, parallel voting 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 (not to be confused with electoral fusion) or majority bonus, another independent mixture of two system but without two tiers. Superposition (parallel voting) 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.
Most often, parallel voting involves combining a winner-take-all system with party-list proportional representation (PR). [1] While first-preference plurality with PR is the most common pairing in parallel voting, many other combinations are possible.
The proportion of list seats compared to total seats ranges widely; for example 30% in Taiwan, 37.5% in Japan and 68.7% in Armenia. [2] Parallel voting is used in both national parliaments and local governments in Italy, Taiwan, Lithuania, Russia, Argentina, and other countries, making it among the world's most popular electoral systems.[ citation needed ]
In parallel voting, voters cast two (or more) votes, one for each method the system contains.[ citation needed ] However, these votes do not interact in any way: the vote in one method has no effect on the calculation of seats in the other methods.
Under the most common form of parallel voting, a portion of seats in the legislature are filled by the single-member first-preference plurality method (FPP), while others are filled by proportional representation. [3] This sometimes leads to a hypercorrection that attempts to limit the term parallel voting to refer only to mixtures of first-past-the-post and proportional representation. Parallel voting can use other systems besides FPP, and can have any mixture of winner-take-all, semi-proportional, and proportional components.
Although the two are often mistakenly conflated, mixed-member majoritarian representation and parallel voting refer to two different things. Parallel voting refers to a rule for computing each party's representation in a legislature, which involves two voting systems operating in parallel, with one being layered (superimposed) on top of the other. By contrast, mixed-member majoritarian representation refers to the results of the system, i.e. the system retains the advantage that some parties parties get in the winner-take-all side of the system.
For this reason, parallel voting is not always mixed-member majoritarian. For example, parallel voting may use a two proportional systems like STV and list-PR and then it would not be mixed-member majoritarian, and a majority bonus system (which is not the same as parallel voting) may also be considered mixed majoritarian. In addition, some mixed-member majoritarian systems are not parallel, in that they allow for interaction (limited compensation) between the two components, for example this is the case in South Korea and Mexico. In South Korea, the hybrid of parallel voting and seat linkage compensation, being between the MMP and MMM type of representation has been called mixed-member semi-proportional representation as well.[ citation needed ]
Unlike mixed-member proportional representation, where party lists are used to achieve an overall proportional result in the legislature, under parallel voting, proportionality is confined only to the list seats. Therefore, a party that secured, say, 5% of the vote will have only 5% of the list seats, and not 5% of all the seats in the legislature.
The major critique of parallel systems is that they cannot guarantee overall proportionality. Large parties can win very large majorities, disproportionate to their percentage vote.
Parallel voting systems allow smaller parties that cannot win individual elections to secure at least some representation in the legislature; however, unlike in a proportional system they will have a substantially smaller delegation than their share of the total vote. This is seen by advocates of proportional systems to be better than elections using only first-past-the-post, but still unfair towards constituents of smaller parties. If there is also a threshold for list seats, parties which are too small to reach the threshold are unable to achieve any representation, unless they have a very strong base in certain constituencies to gain individual seats.
Smaller parties are still disadvantaged as the larger parties still predominate. Voters of smaller parties may tactically vote for candidates of larger parties to avoid wasting their constituency vote. If the smaller party close to the threshold may refrain from voting for their preferred party in favour of a larger party to avoid wasting their list vote as well. In countries where there is one dominant party and a divided opposition, the proportional seats may be essential for allowing an effective opposition.
Those who favour majoritarian systems argue that supplementary seats allocated proportionally increases the chances that no party will receive a majority in an assembly, leading to minority or coalition governments.[ citation needed ]; the largest parties may need to rely on the support of smaller ones in order to form a government. Those who favour proportional representation see this as an advantage as parties may not govern alone, but have to compromise. It is also argued that parallel voting does not lead to the degree of fragmentation found in party systems under pure forms of proportional representation. [4]
Because voters have two votes, one for a constituency candidate and one for a list, there is a critique that two classes of representatives will emerge under a parallel voting system: with one class beholden to their electorate seat, and the other concerned only with their party. Some consider this as an advantage as local as well as national interests will be represented. Some prefer systems where every constituency and therefore every constituent has only one representative, while others prefer a system where every MP represents the electorate as a whole as this is reflected in the electoral system as well.
Parallel systems are often contrasted with mixed-member proportional systems (MMP) or the additional member system (AMS). There are a unique set of advantages and disadvantages that apply to these specific comparisons.
A party that can gerrymander local districts can win more than its share of seats. So parallel systems need fair criteria to draw district boundaries. (Under MMP a gerrymander can help a local candidate, but it cannot raise a major party’s share of seats, while under AMS the effects of gerrymandering are reduced by the compensation)
Japan, and subsequently Thailand and Russia adopted a parallel system to provide incentives for greater party cohesiveness. [5] The party is sure to elect the candidates at the top of its list, guaranteeing safe seats for the leadership. By contrast, under the MMP or AMS system a party that does well in the local seats will not need or receive any compensatory list seats, so the leadership might have to run in the local seats.
Certain types of AMS can be made de facto parallel systems by tactical voting and parties using decoy lists, which (other) MMP systems generally avoid. This specific type of tactical voting does not occur in parallel voting systems as there is no interaction between its systems to exploit in a way that makes it irrelevant. However, other types of tactical voting (such as compromising) are more relevant under parallel voting, than under AMS, and are virtually irrelevant under MMP.[ citation needed ] Tactical voting by supporters of larger parties in favour of allied smaller parties close to a threshold, to help their entry to parliament are a possibility in any parallel, AMS or MMP system with an electoral threshold.
Parallel systems support the creation of single-party majorities more often than MMP or AMS systems, this may be a positive or a negative depending on the view of the voter.
Parallel voting is currently used in the following countries: [6]
The Philippines' electoral system for Congress is an exceptional case. Political parties running for party-list seats are legally required to be completely separate from those running in constituency seats. Furthermore, political parties are capped at 3 seats (out of 61). As a result, the mixed-member system utilized in the Philippines is not representative at all of the share of the vote that "normal" political parties obtain (even amongst mixed-member majoritarian systems), let alone for those in full proportional representation systems.
In New Zealand, the Royal Commission on the Electoral System reviewed the electoral system in 1985–86 and considered parallel voting as a possible replacement for the single-member plurality (SMP) system in use at the time.
The commission came to the conclusion that parallel voting would be unable to overcome the shortcomings of New Zealand's previous SMP system. The total seats won by a party would likely remain out of proportion to its share of votes—there would be a "considerable imbalance between share of the votes and share of the total seats"—and it would be unfair to minor parties (who would struggle to win constituency seats). [16] In the indicative 1992 electoral referendum, parallel voting was one of four choices for an alternative electoral system (alongside MMP, AV and STV), but came last with only 5.5 percent of the vote. An overwhelming majority of voters supported MMP, as recommended by the Royal Commission, and the system was adopted after the 1993 electoral referendum.
In another referendum in 2011, 57.77% of voters elected to keep current the MMP system. Among the 42.23% that voted to change to another system, a plurality (46.66%) preferred a return to the pre-1994 SMP system. Parallel voting was the second-most popular choice, with 24.14% of the vote.[ citation needed ]
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. PR systems provide balanced representation to different factions, 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 additional-member system (AMS) is a two-vote seat-linkage-based mixed electoral system used in the United Kingdom in which most representatives are elected in single-member districts (SMDs), and a fixed number of other "additional members" are elected from a closed list to make the seat distribution in the chamber more proportional to the votes cast for party lists. It is distinct from using parallel voting for the list seats in that the "additional member" seats are awarded to parties taking into account seats won in SMDs – these are ignored under parallel voting.
Mixed-member proportional representation is a type of representation provided by some mixed electoral systems which combine local winner-take-all elections with a compensatory tier with party lists, in a way that produces proportional representation overall. Like proportional representation, MMP is not a single system, but a principle and goal of several similar systems. Some systems designed to achieve proportionality are still called mixed-member proportional, even if they generally fall short of full proportionality. In this case, they provide semi-proportional representation.
First-past-the-post (FPTP)—also called choose-one, first-preference plurality (FPP), or simply plurality—is a single-winner voting rule. Voters mark one candidate as their favorite, or first-preference, and the candidate with the most first-preference marks is elected, regardless of whether they have over half of votes.
Electoral reform in New Zealand has been a political issue in the past as major changes have been made to both parliamentary and local government electoral systems. A landmark reform was the mixed-member proportional (MMP) system, implemented in 1996 following a public referendum.
An electoraldistrict, sometimes called a constituency, riding, or ward, is a geographical portion of a political unit, such as a country, state or province, city, or administrative region, created to provide the voters therein with representation in a legislature or other polity. That legislative body, 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. The district representative or representatives may be elected by single-winner first-past-the-post system, a multi-winner proportional representative system, or another voting method.
A party-list system is a type of electoral system that formally involves political parties in the electoral process, usually to facilitate multi-winner elections. In party-list systems, parties put forward a list of candidates, the party-list who stand for election on one ticket. Voters can usually vote directly for the party-list, but in other systems voters may vote directly for individual candidates within or across party lists, instead of voting directly for parties.
Electoral reform is a change in electoral systems which alters how public desires are expressed in election results.
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 used to determine the results of an election. 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.
A winner-take-all electoral system is one where a voting bloc can win all seats in a legislature or electoral district, denying representation to any political minorities. Such systems are used in many major democracies. Such systems are sometimes called "majoritarian representation", though this term is a misnomer, as most such systems do not always elect majority preferred candidates and do not always produce winners who received majority of votes cast in the district, and they allow parties to take a majority of seats in the chamber with just a minority of the vote.
The dual-member mixed proportional (DMP) voting method is a mixed electoral system using a localized list rule to elect two representatives in each district. It is similar to other forms of mixed-member proportional representation, but differs from the better-known additional-member system in that all representatives are elected locally in small districts, rather than requiring separate list seats to be filled in large regional or nationwide districts. In the first step, one seat in each district is awarded to the candidate or party with the most votes, as with first-past-the-post voting rules. In the second step, underrepresented parties are assigned secondary seats in the districts in which they won the most votes, which creates an overall proportional result.
A mixed electoral system is one that uses different electoral systems to elect different seats in a legislature. Most often, this involves a winner-take-all component combined with a proportional component. The results of the combination may be mixed-member proportional (MMP), where the overall results of the elections are proportional, or mixed-member majoritarian, in which case the overall results are semi-proportional, retaining disproportionalities from the majoritarian component. Systems that use multiple types of combinations are sometimes called supermixed.
Rural–urban proportional representation (RUP), also called flexible district PR, is a supermixed electoral system which combines the use of single- and multi-member constituencies in a lower tier and top-up seats in an upper tier to meet the different needs of both rural and urban areas, while protecting the objective of proportionality. The term was coined by Fair Vote Canada, which devised a rural–urban system with the intention of meeting the special challenges of Canada's geography, which includes wide-flung, sparsely populated areas.
A mixed single vote (MSV) is a type of ballot in mixed-member electoral systems, where voters cast a single vote in an election, which used both for electing a local candidate and as a vote for a party affiliated with that candidate according to the rules of the electoral system. Unlike most mixed proportional and mixed majoritarian systems where voters cast two votes, split-ticket voting is not possible under MSV. This significantly reduces the possibility of manipulating compensatory mixed systems, at the price of reducing voter choice. An alternative based on the mixed single vote that still allows for indicating different preferences on different levels is the mixed ballot, which functions as a preferential (mixed) single vote.
The mixed ballot transferable vote (MBTV) refers to a type of vote linkage-based mixed-member electoral system where a group of members are elected on local (lower) tier, for example in single-member districts (SMDs). Other members are elected on a compensatory national (upper) tier from a list and voters cast a single ballot where they may indicate their preferences separately.
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.
Compensation or correction is an optional mechanism of electoral systems, which corrects the results of one part of the system based on some criterion to achieve a certain result, usually to make it more proportional. There are in general two forms of compensation: vote linkage and seat linkage.
The vote linkage or (multi-tier) vote transfer system is type of compensatory mixed electoral system, where votes may be transferred across multiple tiers of an electoral system, in order to avoid wasted votes - in contrast to the more common seat linkage compensatory system. It often presupposes and is related to the concept of the mixed single vote, which means that the same vote can be used in multiple tiers of an electoral system and that a vote for a local candidate may automatically count as a vote for the candidate's party or the other way around. Voters usually cast their single vote for a local candidate in a single-member district (SMD) and then all the wasted votes from this lower tier are added to distribute seats between upper tier candidates, typically national party lists.