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 (although strictly a poll is an actual election) is a human research survey of public opinion from a particular sample. Opinion polls are usually designed to represent the opinion ...

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

constituency An electoral district, also known as an election district, legislative district, voting district, constituency, riding, ward, division, or (election) precinct is a subdivision of a larger state (a country, administrative region, or other poli ...

based

first past the post In a first-past-the-post electoral system (FPTP or FPP), formally called single-member plurality voting (SMP) when used in single-member districts or informally choose-one voting in contrast to ranked voting, or score voting, voters cast thei ...

system, as in the UK general elections. Under the uniform national swing, changes in the vote proportions (

swing Swing or swinging may refer to: Apparatus * Swing (seat), a hanging seat that swings back and forth * Pendulum, an object that swings * Russian swing, a swing-like circus apparatus * Sex swing, a type of harness for sexual intercourse * Swing ri ...

) 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. However, UNS has proven acceptably accurate in the past, and so is commonly used in UK media for seat count predictions.

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, with 45,597,461 registered voters entitled to vote to elect members to the House of Commons. The election took place in 650 constituencies across the United Kingdom und ...

Political terminology {{Politics-stub