The Mathematics of the General Election

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The Mathematics of the General Election Dr Justin Greaves Department of Politics University of Warwick

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The Mathematics of the General Election. Dr Justin Greaves Department of Politics University of Warwick. Outline of this talk. The basics (background and context) What is a ‘swing’? What is a ‘hung parliament’? The electoral system Opinion polls - PowerPoint PPT Presentation

Transcript of The Mathematics of the General Election

Page 1: The Mathematics of the General Election

The Mathematics of the General Election

Dr Justin Greaves

Department of Politics

University of Warwick

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Outline of this talk

• The basics (background and context)

• What is a ‘swing’?

• What is a ‘hung parliament’?

• The electoral system

• Opinion polls

• The national debt (perhaps the main election issue?)

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So, what are the basics?

• More than 45 million people aged 18 or above vote for a new Member of Parliament (MP) for the area in which they live (Constituency)

• Elections must be held at least every five years in Britain – up to PM to choose the date

• Traditionally held on a Thursday

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Why a Thursday? • One theory about its

origins is that people were not paid until Fridays and so holding polls on Thursdays ensured they were not too drunk to vote

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Two controversial issues

1. Should the voting age be reduced to 16?

2. Should we introduce compulsory voting (as in Australia)?

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The three main parties

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The three party leaders

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The TV debates• This is the first

election in the UK where there have been TV debates between the three party leaders

• Here is a clip from the 2nd debate

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Too much celebrity?• Is it becoming too

much like the X Factor or Britain’s Got Talent?

• Leaders judged on how good they look on TV?

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So now onto the maths ....

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What is a ‘swing’? • Swing is a tool which

helps explain how elections are won and lost

• In simple terms it is a way of measuring how the public's support of political parties changes from one election to the next

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The calculation

• Step 1. Add the rise in one party's share in the vote to the fall in the second party's share of the vote.

• Step 2. Divide your figure by two. The resulting figure is the swing.

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An example

• In the 2005 General Election the Labour Party had a lead of 3% over the Conservative Party

• Let’s assume that in Thursday’s election, the result is a Con lead of 4% over Labour

• Exercise: calculate the swing

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The answer• This is a swing of

3.5% (3+4/2).

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What to look out for• 1.6% swing against Labour: Labour lose

their overall majority • 4.3% swing against Labour: The

Conservatives become the largest party. They would still not have an overall majority.

• 6.9% swing against Labour: The Conservatives gain an overall majority and therefore form the next government(but will a UNS operate?)

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What is a ‘hung parliament’?

• If one party has an absolute majority it means that it has more seats than all the other parties put together (326+)

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• If no party has such a majority then there is a hung parliament

• The smaller parties can then join forces to out-vote the government

• This makes it difficult to pass laws

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• There is a good

chance of a hung parliament resulting from this election

• The last time it happened was in February 1974

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Options in a hung parliament

• Formal coalition (alliance with another party)

• Confidence and supply

• Minority government

• If none of these options work there would have to be another election

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Why is it so rare?

• Hung Parliaments and coalitions happen a lot in other countries

• So why are they so rare in the UK?

• This is mainly a result of our electoral system

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Proportional Representation

• Many countries have a proportional electoral system (eg: under PR if a party wins 30% of the votes, it will win approx 30% of the seats)

• It is rare for any one party to get over 50% of the vote

• Therefore, in these countries parties will have to work together

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First past the post• Britain has a first past the post electoral

system• Therefore, 650 constituencies• In each one, the candidate who gets the

most votes wins (even if it is less than 50%)

• EG: if the winner gets 36% of the vote they still take the seat

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• It is like a horse race• The winner of the

race is the first to pass a particular point on the track

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Strange results

• FPP can throw up strange results:

1.A party with 35/40% support can get well over 50% of the seats

2.The party that wins most votes may not win most seats (eg: 1974)

3.The Lib Dems could come first in vote share and third in seats

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Opinion polls

• You may have seen opinion polls in the media

• These may only interview 1000 people out of the whole population of Britain

• If the sample is ‘representative’ these polls should be accurate

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• Polls usually have a

margin of error of + or – 3%

• 19 times out of 20 a poll should fall between this margin of error

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Think, pair, share• What could cause

an opinion poll to be biased or skewed in some way?

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National debt and borrowing• One of the biggest

election issue is the amount of money the government is borrowing (and Britain’s national debt)

• Due to the recession the government had to borrow a lot of money

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• One reason was to

rescue the banks

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• Another was to pay

benefits to those who became unemployed

• And if people are out of work the government also loses tax revenue

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Party Policy

• The Labour Party plans to reduce the amount we borrow by 50% over four years (starting in 2011)

• The Conservative Party say this is not enough. They want to go cut faster and deeper

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Debt statistics• Borrowing of £163

billion last year• The government

forecasts that debt will soar to £1.1 trillion by 2011

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Debt statistics (2)• We owe £14,480 for

every man, woman and child

• That's more than £31,254 for every person in employment

• Every household will pay £1,898 this year, just to cover the interest

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Thank you for listening