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September 12, 2020 - Comments Off on Politics, Elections and Geography

Politics, Elections and Geography

19th February 2020

Coursework 1: Politics, Elections and Geography

This report will describe an investigation into the space of visually communicating political election results. It will focus on how, by incorporating geographical data, the presentation of election outcomes is sometimes distorted. These misrepresentations may be either unintended or deliberate. For simplicity and brevity, the scope of the investigation will focus on the UK and US electoral systems.

The UK and US electoral systems generally follow the first past the post system – also more accurately described as a single-member plurality (Gallagher and Mitchell 18). In a first past the post system, a voter selects one of the candidates listed on the ballot. The person with the plurality of votes wins, and all other votes are disregarded (Govt of NZ). Both the UK Parliament and the US House of Representatives following a similar system. Each nation is divided into geographical areas known as parliamentary constituencies or congressional districts. The UK has 650 constituencies (‘UK Constituencies’), and the US has 450 districts (‘US Districts’). Both the UK and the US have two-party systems, and as Duverger postulated, first past the post electoral systems tend to encourage a two-party system (Grofman et al. 4). The main parties in the UK are the Labour and Conservative parties and, in the US, the Republican and Democrat parties. However, regional differences in the UK also tend to reflect additional party representation (Blumenau and Hix). One important difference is the election of the head of government. The UK Prime Minister is typically the leader of the party in government (‘PM of the UK’). The US President is chosen by the members of the Electoral College. Each State chooses a number of Electors, equal to States two Senators and the allotted Representatives for that State (National Archives). Therefore, there are 538 Electors, including three allocated to the District of Columbia) Typically, the Electors are chosen, based on the state-wide first past the post system on the Presidential election day. Maine and Nebraska are the only two exceptions as both states allocate Electors based on congressional districts (‘US Electoral College’). Thus, voters vote for a Presidential candidate on the ballot paper, are in fact voting for an Elector, who in turn votes for the winning candidate for President in their State (except for Maine and Nebraska). So, conceptually, we have similar data spaces between both the UK and US electoral systems - around 500 representative choices with 2-8 possible results, and one overall outcome. The next section will discuss visualisation examples that have used to illustrate that data space.

Fig 1: US 2012 Election Results

As a starting point, a Google image search was conducted of the last two elections for the UK and US. The string for the search was as depicted in the figure titles. The first ~15 results for each search are shown in Fig 1 through Fig 4.

Fig 2: US 2016 Election Results

Fig 3: UK 2017 Election Results

A close up of a map

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Fig 4: UK 2019 Election Results

The majority of the images of the US is that of a choropleth[1] – where each state is coloured according to whether the Democrats or Republican prevailed. The issue with that representation is that the area of a state is not proportionate to the number of electoral college votes allocated to that state. For example, Montana is 2000 times the area of the District of Columbia, but both have the same number of electoral votes. Only one image, a cartogram[2] in Fig 1, attempted to graphically show the relative number of electoral college votes that each candidate received. Choropleths seem optimised for display theme information. (Rittschof and Kulhavy 37). Perhaps the main theme of such maps is to show which way an individual state or area voted. That said, by viewing the choropleths in Fig 1, it would be reasonable for a reader to misinterpret the outcome of the 2012 election - to believe Romney won and not Obama.

Interestingly the UK election results shown in Fig 3 and Fig 4 are more likely to adopt a cartogram approach. Perhaps since UK constituencies are more numerous, it would be hard to find one from 650 in such a representation? Although the approach seems to reflect the overall parliamentary distribution better, it still seems hard to determine the governmental outcome without additional information. The issue of effectively conveying election results has been discussed in several articles. The next section will discuss a few remedies that that be proposed to address the issue.

One critique of the choropleth maps is that “land doesn’t vote, people do”. On October 1st 2019, Trump tweeted the following: A close up of a map

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Fig 5: Trump October 2019 Tweet

The implication being that most of the country voted for Trump in 2016. This was incorrect (CNN). Other representations have been proposed, which more accurately reflect voter participation (Knudsen) - see Fig 6. This map shows a circle, sized on county population and coloured relative to candidate choice. However, this presentation also suffers from incorrectly representing the electoral outcome - electoral college votes are apportioned by population (one per district) as well as by area (two per state). Perhaps a better representation can be found?

A close up of a logo

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Fig 6: 2016 Voter by County

The Financial Times has undertaken the “search for a better US election map”. They argued that although the choropleth has become the default representation of US elections, it is arguably a deeply flawed map. (Pearson et al.). Their final compromise was a proportional symbol map, where the number of State allocated electoral college votes was coloured for each candidate, as shown below.

A picture containing text

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Fig 7: 2012 Electoral Vote by State

It seems to facilitate the task of determining which candidate prevailed in a State as well as giving a better overview of the nationwide electoral college vote.

In conclusion, in order to visually describe an electoral outcome more effectively, it is important to understand the electoral system and how the winner is determined. It’s not necessarily just about one person one vote. In the US the electoral college votes for the president and those members are allocated based on population and state boundaries. In terms of visual presentation, while the UK seems to be moving towards a cartographic presentation of electoral results, there seems to be no such trend in the US. The US seems to favour a choroplethic presentation.

A close up of a map

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Fig 8: Financial Times 2016 Results combined with Trump Tweet


Blumenau, Jack, and Simon Hix. ‘Britain’s Evolving Multi-Party System(s)’. British Politics and Policy at LSE, 31 Mar. 2015,

CNN. Trump’s Impeachment Tweet of a 2016 Election Map Is Inaccurate. Here’s Why - CNN Video., Accessed 18 Feb. 2020.

Gallagher, Michael, and Paul Mitchell. The Politics of Electoral Systems. OUP Oxford, 2005.

Govt of NZ, The Department of Internal. More about FPP. Accessed 18 Feb. 2020.

Grofman, Bernard, et al. Electoral Laws and Their Political Consequences. Algora Publishing, 1986.

Knudsen, Nick. ‘Land Doesn’t Vote, People Do: This Electoral Map Tells the Real Story’. DemCast, 11 Nov. 2019,

National Archives. ‘Legal Provisions Relevant to the Electoral College Process’. National Archives, 5 Sept. 2019,

Pearson, Tom, et al. The Search for a Better US Election Map. 8 Nov. 2016,

‘PM of the UK’. Wikipedia, 15 Feb. 2020. Wikipedia,

Rittschof, Kent A., and Raymond W. Kulhavy. ‘Learning and Remembering from Thematic Maps of Familiar Regions’. Educational Technology Research and Development, vol. 46, no. 1, Mar. 1998, pp. 19–38. (Crossref), doi:10.1007/BF02299827.

‘UK Constituencies’. Wikipedia, 16 Feb. 2020. Wikipedia,

‘US Districts’. Wikipedia, 10 Dec. 2019. Wikipedia,

‘US Electoral College’. Wikipedia, 18 Feb. 2020. Wikipedia,

  1. Choropleth maps are based on data properties applied to a defined area, for example, a US State.
  2. A cartogram is a map in which the data property – such as the number of electoral college votes – is substituted for a defined area or distance.