Mixed-member majoritarian representation

Mixed member majoritarian representation (MMM) is type of a mixed electoral system combining majoritarian and proportional methods, where the disproportional results of the majoritarian side of the system prevail over the proportional component. Mixed member majoritarian systems are therefore also as a type of semi-proportional representation, and are usually contrasted with mixed-member proportional representation (MMP) which aims to provide proportional representation via additional compensation ("top-up") seats. The most common type of MMM system is called parallel voting also, known as the supplementary member (SM) system, whereby representatives are voted into a chamber using at least two different systems independently of each other. Most commonly this combines first-past-the-post (single member plurality) voting (FPTP/SMP) with party-list proportional representation (list-PR). The system has been applied in the election of national parliaments as well as local governments in various places such as Taiwan, Lithuania and Russia. While FPTP with list-PR is the most common pairing in parallel systems, any other combination is effectively possible and therefore not all parallel voting systems are mixed-member majoritarian, however as most of them used in practice are, the terms are sometimes used interchangeably. According to the academic typology of Massicotte & Blais (1999), mixed-member majoritarian versions come in the following forms: Superposition, or the supplementary member (SM) system where two different systems are used on different levels of the electoral system in a non-compensatory manner. This means if a party gets a disproportionally high share of seats in the majoritarian tier, they retain this absolute advantage even as their relative (percentage-wise) advantage may decrease due to a proportional component. Parallel voting is defined by the voter having two votes and there being no interaction between the two (or more) component systems of the election, like the two-round system and list-PR (Lithuania) or party block voting and list-PR (Andorra).