Plurality voting refers to electoral systems in which the candidates in an electoral district who poll more than any other are elected.
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.
The single transferable vote (STV) or 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 ballot. Voters have the option to rank candidates, and their vote may be transferred according to alternative 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 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.
The alternative vote plus (AV+), or alternative vote top-up, is a semi-proportional voting system. AV+ was devised by the 1998 Jenkins Commission which first proposed the idea as a system that could be used for elections to the Parliament of the United Kingdom.
Historically, the single transferable vote (STV) electoral system has seen a series of relatively modest periods of usage and disusage throughout the world; however, today it is seeing increasing popularity and proposed implementation as a method of proportional representation and a goal of electoral reform. STV has been used in many different local, regional and national electoral systems, as well as in various other types of bodies, around the world.
Scotland has elections to several bodies: the Scottish Parliament, the United Kingdom Parliament, local councils and community councils. Before the United Kingdom left the European Union, Scotland elected members to the European Parliament.
The 2011 Scottish Parliament election was held on Thursday, 5 May 2011 to elect 129 members to the Scottish Parliament.
The 2007 Scottish Parliament election was held on Thursday 3 May 2007 to elect members to the Scottish Parliament. It was the third general election to the devolved Scottish Parliament since it was created in 1999. Local elections in Scotland fell on the same day.
There are a number of complications and issues surrounding the application and use of single transferable vote proportional representation that form the basis of discussions between its advocates and detractors.
Electoral reform is a change in electoral systems which alters how public desires are expressed in election results.
There are five types of elections in the United Kingdom: elections to the House of Commons of the United Kingdom, elections to devolved parliaments and assemblies, local elections, mayoral elections, and Police and Crime Commissioner elections. Within each of those categories, there may also be by-elections. Elections are held on Election Day, which is conventionally a Thursday, and under the provisions of the Dissolution and Calling of Parliament Act 2022 the timing of general elections can be held at the discretion of the prime minister during any five-year period. All other types of elections are held after fixed periods, though early elections to the devolved assemblies and parliaments can occur in certain situations. The five electoral systems used are: the single member plurality system (first-past-the-post), the multi-member plurality, the single transferable vote, the additional member system, and the supplementary vote.
The United Kingdom Alternative Vote referendum, also known as the UK-wide referendum on the Parliamentary voting system was held on Thursday 5 May 2011 in the United Kingdom to choose the method of electing MPs at subsequent general elections. It occurred as a provision of the Conservative–Liberal Democrat coalition agreement drawn up in 2010 and also indirectly in the aftermath of the 2009 expenses scandal. It operated under the provisions of the Parliamentary Voting System and Constituencies Act 2011 and was the first national referendum to be held under provisions laid out in the Political Parties, Elections and Referendums Act 2000. Many local elections were also held on this day.
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.
The 2016 Scottish parliament election was held on Thursday, 5 May 2016 to elect 129 members to the Scottish Parliament. It was the fifth election held since the devolved parliament was established in 1999. It was the first parliamentary election in Scotland in which 16 and 17 year olds were eligible to vote, under the provisions of the Scottish Elections Act. It was also the first time the three largest parties were led by women.
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.
The next Scottish Parliament election is required to be held no later than Thursday 7 May 2026, to elect 129 members to the Scottish Parliament. It will be the seventh general election since the parliament was re-established in 1999.
Elections to Dumfries and Galloway Council took place on 5 May 2022 on the same day as the 31 other Scottish local government elections. As with other Scottish council elections, it was held using single transferable vote (STV) – a form of proportional representation – in which multiple candidates are elected in each ward and voters rank candidates in order of preference.
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.
