Approval voting is a single-winner rated voting system in which voters mark all the candidates they support, instead of just choosing one. It is a form of score voting where only two scores are allowed: 0 and 1 (approved). The candidate with the highest approval rating is elected. Approval voting is currently in use for government elections in St. Louis, Missouri, USA, Fargo, North Dakota, USA, and in the United Nations to elect the Secretary General.
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.
A political party is an organization that coordinates candidates to compete in a particular country's elections. It is common for the members of a party to hold similar ideas about politics, and parties may promote specific ideological or policy goals.
Score voting, sometimes called range voting, is an electoral system for single-seat elections. Voters give each candidate a numerical score, and the candidate with the highest average score is elected. Score voting includes the well-known approval voting, but also lets voters give partial (in-between) approval ratings to candidates.
The two-round system, also called ballotage, top-two runoff, or two-round plurality, is a single winner voting method. It is sometimes called plurality-runoff, although this term can also be used for other, closely-related systems such as instant-runoff voting or the exhaustive ballot. It falls under the class of plurality-based voting rules, together with instant-runoff and first-past-the-post (FPP). In a two-round system, if no candidate receives a majority of the vote in the first round, the two candidates with the most votes in the first round proceed to a second round where all other candidates are excluded. Both rounds are held under choose-one voting, where the voter marks a single favored candidate.
A two-party system is a political party system in which two major political parties consistently dominate the political landscape. At any point in time, one of the two parties typically holds a majority in the legislature and is usually referred to as the majority or governing party while the other is the minority or opposition party. Around the world, the term has different meanings. For example, in the United States, the Bahamas, Jamaica, and Zimbabwe, the sense of two-party system describes an arrangement in which all or nearly all elected officials belong to either of the two major parties, and third parties rarely win any seats in the legislature. In such arrangements, two-party systems result from Duverger's law, which states that winner-take-all systems tend to produce two-party systems.
Voting refers to the process of choosing officials or policies by casting a ballot, a document used by people to formally express their preferences. Republics and representative democracies are governments where the population chooses representatives by voting.
A party system is a concept in comparative political science concerning the system of government by political parties in a democratic country. The idea is that political parties have basic similarities: they control the government, have a stable base of mass popular support, and create internal mechanisms for controlling funding, information and nominations.
In social choice theory, the majority rule (MR) is a social choice rule which says that, when comparing two options, the option preferred by more than half of the voters should win.
Single-issue politics involves political campaigning or political support based on one essential policy area or idea.
Bipartisanship, sometimes referred to as nonpartisanship, is a political situation, usually in the context of a two-party system, in which opposing political parties find common ground through compromise. In multi-partisan electoral systems or in situations where multiple parties work together, it is called multipartisanship. Partisanship is the antonym, where an individual or political party adheres only to its interests without compromise.
The ley de lemas is a variant of open list proportional representation, which is, or has been, used in elections in Argentina, Uruguay, and Honduras, and works as follows:
In political science and sociology, a cleavage is a historically determined social or cultural line which divides citizens within a society into groups with differing political interests, resulting in political conflict among these groups. Social or cultural cleavages thus become political cleavages once they get politicized as such. Cleavage theory accordingly argues that political cleavages predominantly determine a country's party system as well as the individual voting behavior of citizens, dividing them into voting blocs. These blocs are distinguished by similar socio-economic characteristics, who vote and view the world in a similar way. It is distinct from other common political theories on voting behavior in the sense that it focuses on aggregate and structural patterns instead of individual voting behaviors.
Proportionality for solid coalitions (PSC) is a criterion of proportionality for ranked voting systems. It is an adaptation of the quota rule to voting systems in which there are no official party lists, and voters can directly support candidates. The criterion was first proposed by the British philosopher and logician Michael Dummett.
Direct representation or proxy representation is a form of representative democracy where voters can vote for any candidate in the land, and each representative's vote is weighted in proportion to the number of citizens who have chosen that candidate to represent them.
The binomial system is a voting system that was used in the legislative elections of Chile between 1989 and 2013.
There are a number of different criteria which can be used for voting systems in an election, including the following
Proportional approval voting (PAV) is a proportional electoral system for multiwinner elections. It is a multiwinner approval method that extends the D'Hondt method of apportionment commonly used to calculate apportionments for party-list proportional representation. However, PAV allows voters to support only the candidates they approve of, rather than being forced to approve or reject all candidates on a given party list.
The 1994 electoral reform in Japan was a change from the previous single non-transferable vote (SNTV) system of multi-member districts (MMD) to a mixed electoral system of single-member districts (SMD) with plurality voting and a party list system with proportional representation. The reform had three main objectives: change the one-party dominance of the Liberal Democratic Party (LDP) from the previous 1955 system to a two-party system with alternation in power, reduce the cost of elections and campaigns, and change campaign focus from individual-centered to party-centered.
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