Editing Single transferable vote (section)

==Related voting systems==
[[Instant-runoff voting]] (IRV) is the single-winner analogue of STV. It is also called ''single-winner ranked-choice voting'' and ''preferential voting''. Its goal is representation of a majority of the voters in a district by a single official, as opposed to STV's goals of not only the representation of a majority of voters through the election of multiple officials but also of proportional representation of all the substantial voting blocks in the district.

[[Single non-transferable vote]] (SNTV) produces much the same representation as STV, without the work and complication of preferential ballots and vote transfers. Single voting in a multiple-member district produces mixed roughly proportional representation, which STV's vote transfers sometimes does not alter. (An example was the [[1930 Alberta general election|election of Edmonton, Alberta, MLAs through STV in 1930]]. The winners were the same under STV as would have been elected under SNTV.)

The [[spare vote]]<ref>Björn Benken: [http://www.dualvoting.com/ ''What is Dual Level Voting?''], retrieved on 14 May 2022.</ref> is a version of single transferable voting applied to the ranking of parties, first proposed for elections in Germany in 2013.<ref name="first">German state parliament faction of the pirates in Schleswig-Holstein: [http://www.landtag.ltsh.de/infothek/wahl18/umdrucke/1900/umdruck-18-1916.pdf ''Alternativen zum Gesetzentwurf aus Drucksache 18/385''], 4 November 2013, in German</ref> The spare vote system includes the step of transferring the votes of eliminated choices to the next-indicated choice, but it does not transfer surplus votes.

The [[mixed ballot transferable vote]] (MBTV) is a [[Mixed electoral system|mixed]] version of STV, where voters may rank both candidates and parties, even both interchangeably, depending on the ballot type, but must choose at least a local (district) candidate (1st preference) and a national list (2nd preference). The list preferences are used if the vote is unused in the district election, which may use FPTP, IRV or STV rules; in the STV case, the vote is transferred to another tier in favour of the chosen party list. (This is in contrast to the [[mixed single vote]], which is currently used in Hungary, where voters may not define a separate party-list preference and do not cast preferential votes.)

[[Indirect single transferable voting]] is a non-ranked-vote version of STV. Single voting in a multi-seat district is retained. Voters do not mark their ballots with rankings, but votes are transferred, as needed, based on the eliminated or elected candidate's pre-set instructions. This is a useful system to achieve many of the benefits of STV in districts where it is difficult to collect all the ballots in one central place to conduct STV transfers or where X voting is preferred over ranked voting due to voters' inability or disinterest in ranking candidates. Once known as the Gove system, or the schedule system of PR, it was invented by [[1904 Massachusetts legislature|Massachusetts]] legislator William H. Gove of Salem and Archibald E. Dobbs of Ireland, author of ''Representative Reform for Ireland'' (1879).<ref>{{cite report |url=https://www.cs.jhu.edu/~jason/papers/eisner.istv91.pdf |title=Indirect STV Election: A Voting System for South Africa |first=Jason |last=Eisner |access-date=27 February 2023 |date=2015}}</ref><ref>Hoag, Effective Voting (1914)</ref> In 1884, Charles L. Dodgson (Lewis Caroll) argued for a proportional representation system based on multi-member districts similar to indirect STV, with each voter casting only a single vote, quotas as minimum requirements to take seats, and votes transferable by candidates through what is now called [[liquid democracy]]. The difference from "indirect STV" is that under liquid democracy, candidates, elected members and sometimes voters may transfer votes after the votes are cast to build coalitions; candidates do not have to publish their list beforehand.

The [[modified d'Hondt electoral system]]<ref>Australian Capital Territory Electoral Commission, [https://www.elections.act.gov.au/elections_and_voting/past_act_legislative_assembly_elections/modified_dhondt_electoral_system Modified d'Hondt Electoral System] {{Webarchive|url=https://web.archive.org/web/20220920173142/https://www.elections.act.gov.au/elections_and_voting/past_act_legislative_assembly_elections/modified_dhondt_electoral_system |date=20 September 2022 }}</ref> is a variant of STV, where an [[electoral threshold]] for parties is applied.

Two-vote [[Mixed-member proportional representation|MMP]] and [[additional member system]] systems may also be interpreted as a related, effectively preferential mixed system. Votes are not transferred, but a voter may vote differently for the local election and the overall party vote, with one, both or neither of those votes electing someone.<ref>{{cite web | url=https://elections.nz/democracy-in-nz/what-is-new-zealands-system-of-government/what-is-mmp/ | title=What is MMP? }}</ref>

There are also several proportional [[multiwinner approval voting]] rules behaving similarly to STV, for instance the [[method of equal shares]], which also sequentially selects candidates and reweights the voters approving these selected candidates.<ref>{{Cite book|last1=Peters|first1=Dominik|last2=Skowron|first2=Piotr|title=Proceedings of the 21st ACM Conference on Economics and Computation |chapter=Proportionality and the Limits of Welfarism |series=EC'20|year=2020|pages=793–794|doi=10.1145/3391403.3399465|isbn=9781450379755|s2cid=208291203|arxiv=1911.11747}}</ref><ref>{{cite book|last1= Lackner |first1= Martin |last2=Skowron|first2=Piotr|title= Multi-Winner Voting with Approval Preferences |chapter=|series= SpringerBriefs in Intelligent Systems |year=2023|doi= 10.1007/978-3-031-09016-5 |arxiv=2007.01795|isbn= 978-3-031-09015-8 |s2cid= 244921148 }}</ref>