3-Party Swingometer

The BBC coverage of UK elections is well-known for its use of the Swingometer. The Swingometer represents parliamentary constituencies as points on a line. A central point represents equality between the two major parties: the Labour Party (red, politically centre-left) and the Conservative Party (blue, politically centre-right). How far from that central point the seat is to the left or right denotes how strongly that seat is held by Labour or the Conservatives respectively, and how big a shift in opinion is required for the seat to fall into the other party’s hands.

However, if two parties can be compared one-dimensionally, then three parties can be compared two-dimensionally. In many ways, the UK has a three-party parliamentary system. The Liberal Democrats hold a position in UK politics far stronger than any other party that would be considered ‘others’ (see political notes below). It is not inconceivable that at some future point the Liberal Democrats could displace one of the two major parties, and after the upcoming general election their roll could be the most significant for a generation if – as the polls have been predicting – the UK experiences a hung-parliament.

This small application was the product of a day or so prototyping, using Bit 101′s Minimal Components and RobotLegs to see if I could come up with something a bit more interesting than theBBC’s online Swingometer. It lacks the BBC’s finesse (which is unsurprising for a very quick prototype), but I think it is rather more fair to the Liberal Democrats.

Political Notes

Several smaller parties exist, notably the Scottish National Party and Plaid Cymru, the Welsh nationalists. However, these do not have UK-wide reach, and swings to or from either party will not have large national implications, simply because the populations of Scotland and Wales are so much smaller than that in England.

Northern Ireland politics is also omitted from this graph. The source data did not contain Northern Ireland data, but I have not sought to add it either, since Northern Ireland has a quite different political system which is largely based on religious and cultural social differences; the trends in the rest of the UK do not apply to Northern Ireland, and vice versa. Its data would be trivial for the purposes of this visualisation.

Apparently, the change of popularity in the Liberal Democrats has caused the BBC to change its use of the swingometer over the years. They reduced the role of the swingometer as the Liberal Democrats’ power grew in the seventies, and reintroduced it as it waned in the eighties and nineties. Now, the current implementation on their website has three swingometers that can be tabbed between. It is strange then that they haven’t chosen to adopt a more sophisticated representation.

The source data that I used for this application can be found at pippanorris.com. The limitations of the data is most evident in the 1997 election data. The landslide Labour victory is masked by the omission of most of the Scottish constituencies. The problems with historical data are frustrating. If any better data source is known, I would love to know of it.