Proportional Representation

Simply put, Proportional Representation (PR) drives to ensure the number of seats given to a party in an election is in proportion to the popular vote (i.e., the total number of votes received).  In our current system, referred to as First Past the Post, proportionality is rarely achieved.  It is said, that as a result of this discontinuity, there is increased voter apathy from which follows lower voter turnout.  Low voter turnout leads to governments being elected with a very small proportion of the voting public.  For example, in Canada majority governments are often elected with less the 40% of the popular vote.  At 60% participation that means that a government can be elected with support from 24% of the voting pubic, leaving 75% un-represented.  

It is important to keep in mind that there are different approach to PR (Proportional Representation), each having corresponding advantages and disadvantages.  As such, the choice should be arrived at through some assessment of what is locally acceptable and constitutes an appropriate balance.  John Cleese talks about one method that is considered appropriate for the UK.

A Party Political Broadcast from around 1987, featuring John Cleese talking about Proportional Representation, with a little bit of David Owen thrown in. Very funny and a good basic guide as to why PR is a good thing.

A more formal description is offered in Wikipedia:

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“There are two PR voting types: party list PR and the single transferable vote (STV). Mixed member proportional representation (MMP), a hybrid method that uses party list PR as its proportional component, is also usually considered a distinct PR method.

With party list PR, political parties define candidate lists and voters vote for a list. The relative vote for each list determines how many candidates from each list are actually elected. Lists can be “closed” or “open”; open lists allow voters to indicate individual candidate preferences and vote for independent candidates. Voting districts can be as large as a province or an entire nation.

The single transferable vote uses smaller districts, with voters ranking individual candidates in order of preference. During the count, as candidates are elected or eliminated, surplus or discarded votes that would otherwise be wasted are transferred to other candidates according to the preferences. STV enables voters to vote across party lines and to elect independent candidates.

Mixed member proportional representation (MMP), also called the additional member system (AMS), is a hybrid, two-tier, system combining a non-proportional single-winner election and a compensatory regional or national party list PR one. Voters have two votes, one for their single-member district and one for the party list, the party list vote determining the balance of the parties in the elected body. Biproportional apportionment, first used in Zurich in 2006, is a two-tier method for adjusting an election’s result to achieve overall proportionality. A further system produces near perfect proportionality by dispensing with voting altogether: the random selection of representatives from the populace, known as sortition. It was used in ancient Athens and the Venetian Republic and is still used today in the summons to jury duty. In recent years, it has received increasing academic attention.”

— https://en.wikipedia.org/wiki/Proportional_representation