Uniform national swing, or UNS is a system for translating

opinion poll An opinion poll, often simply referred to as a survey or a poll, is a human research survey of public opinion from a particular sample. Opinion polls are usually designed to represent the opinions of a population by conducting a series of qu ...

s, which give overall vote proportions, to expected eventual parliamentary seats in a

constituency An electoral (congressional, legislative, etc.) district, sometimes called a constituency, riding, or ward, is a geographical portion of a political unit, such as a country, state or province, city, or administrative region, created to provi ...

based

first past the post First-past-the-post (FPTP)—also called choose-one, first-preference plurality (FPP), or simply plurality—is a single-winner voting rule. Voters mark one candidate as their favorite, or First-preference votes, first-preference, and the cand ...

system, as in the UK general elections. Under the uniform national swing, changes in the vote proportions ( swing) since the previous election are assumed to be constant across all constituencies. By applying this change to the previous per-constituency based vote proportions, a prediction for which party would have the most votes in each constituency may be made, which is then counted and totalled for a final seat count. Alternative methods exist, such as the proportional national swing system. According to

Peter Kellner Peter Jon Kellner (born 2 October 1946) is an English journalist, former BBC ''Newsnight'' reporter, political commentator, and former president of the YouGov opinion polling organisation in the United Kingdom. He is known for his appearances ...

, UNS has a mixed record of success at predicting seat counts in the UK.

References

External links

BBC seat calculator using UNS
for the

2010 United Kingdom general election The 2010 United Kingdom general election was held on Thursday 6 May 2010, to elect 650 Members of Parliament (or MPs) to the House of Commons of the United Kingdom, House of Commons. The first to be held after the minimum age for candidates was ...

{{Poli-term-stub Political terminology