General Election 2019 Stat Checks: Week One

Parliament has been dissolved, and the campaign formally starts.

This article looks at the various statistics and claims I have checked in the first formal week of campaigning for the 2019 General Election. A letter from Sir David Norgrove, chair of the UK Statistics Authority, was sent to all party leaders:

I would ask that statistical sources should be clear and accessible to all; any caveats or limitations in the statistics should be respected; and campaigns should not pick out single numbers that differ from the picture painted by the statistics as a whole.

5m Labour Leave voters?

Claim: 5m people voted Leave in 2016 and Labour in 2017.
Rating: Needs clarification.
Reasoning: Nigel Farage MEP, Brexit Party leader, has repeated his claim that 5m people voted Leave in 2016 and Labour in the 2017 General Election:

Those five million are the most vulnerable group of voters to the Brexit Party in this country.

Various survey estimates suggest this figure is less than four million. Moreover, not all of these voters will reside in Labour-held constituencies.

We can look at what estimated proportion of Labour voters in 2017 also voted Leave in 2016. In the British Election study face-to-face survey: about 30% of Labour voters backed Leave, or 3.9m voters. Sampling error means this projection ranges from 3.4m to 4.4m.

Of those that voted in both elections, an estimated 23% of Leave voters backed Labour in 2017. (Image: BBC)

Surveys provide estimates, subject to multiple source of potential error. How the Brexit Party leader has calculated his figure needs explanation.


Claim: A majority of Times reader support the Liberal Democrats.
Rating: Needs clarification.
Reasoning: An annotated image from YouGov makes various claims.

The writing is quite small. (Image: Twitter/FreitagWolf)

A self-selecting website survey does not tell us what Times readers think. 48% is a plurality, not a majority.

The suggestion that the Liberal Democrats can beat both Labour and the Conservatives is based on their one point lead in YouGov polling amongst the fragmented Remain vote. There is, however, a slightly larger part of the electorate called Leave voters.

The stated figures from Opinium are also incorrect or out-of-date. In their internet panel polling on 23rd — 25th October, we can look at the sub-sample of recalled 2017 Labour voters. In the question on approval of party leaders, estimated net approval of Swinson was at -5, and Corbyn at -11.

The main challenger

Claim: The Greens are the ‘main challenger’ in the Isle of Wight, based on European Parliament election results.
Rating: Likely to be misleading.
Reasoning: In the last General Election, the Greens were third in the Isle of Wight constituency (on 17.3%). In the European Parliament elections in 2019, the Greens were second (16.5%) in the counting area — compared to the Liberal Democrat vote share of 15.8%.

The Greens are now the ‘Unite to Remain’ candidate in this constituency. (Image: Facebook/Isle of Wight Green Party)

The presentation is likely to be misleading, as the rosettes show the rank — and their size bears no relationship to vote share.

The European Parliament results may also tell us little about the upcoming General Election. The electorate is different. The voting system is different. The competing parties are different, with different strengths. Campaigning is different. UKIP got the most votes in the 2014 European Parliament elections, but only one seat in the 2015 General Election.

The Young Ones

Claim: Labour is polling 7 points behind the Conservatives. At the same point in 2017, Labour were 24 points behind “with one pollster”.
Rating: Likely to be misleading.
Reasoning: On Twitter, author Liam Young states:

Labour has hit its highest polling level since May and is 7% behind the Tories. At the same point in 2017 we were 24% behind with one pollster.

This is highly selective. The former claim comes from the ICM Unlimited poll on 1st — 4th November. The vote intention estimates were Labour on 31% (the highest such reading since a Survation poll in late May), and the Conservatives on 38%. The Conservative lead was estimated at 7 points, the lowest estimate since the House of Commons voted for an early election.

Note that, as the Conservative vote intention estimate went up by two points from ICM’s prior poll in early October, their estimate of the Conservative lead increased.

Young then compares that lead to a Kantar poll on 27th April — 2nd May 2017. At 24 points, this Kantar poll estimated one of the highest leads recorded in 2017.

The comparison of two different survey estimates, from different companies with different methods — one a recent low, the other a past high— is likely to be misleading.

Figures on the bus go round and round

Claim: “We’ll send Trump £500 million a week. Let’s fund US drug firms, not our NHS.” Labour leader Jeremy Corbyn describes £500m a week as an “accurate and credible” figure.
Rating: False.
Reasoning: This claim was made by Labour on Facebook, in a mocked-up version of the Vote Leave battle coach.

‘Let’s give up control.’ (Image: Facebook/Labour)

As BBC Reality Check identified, this figure comes from the following calculation:

  • Currently, the NHS England spend around £18bn on pharmaceutical prescription costs (£18.2bn in 2017/18).
  • The United States spends an average 2.5 times the UK, per person, on medicinal drugs. This factor comes from the OECD, as the BBC reported.
  • Multiplying £18bn by 2.5 gives £45bn.
  • The difference is £27bn, or £519m a week.

The purpose of this calculation was to illustrate differences in pharmaceutical costs between the UK and the US. It does not model the effects of a UK-US trade deal.

According to Dr Andrew Hill (University of Liverpool), it was a “worst case scenario” to “crudely estimate” how much NHS England prescriptions would rise to if the UK matched US pharmaceutical costs per person.

Jeremy Corbyn, Labour leader, claimed he believed it was “an accurate and credible figure”:

I’m very happy for anybody else to analyse it and tell me if I’ve understated the case.

It is false to assert that it was a credible estimate of the effects of UK-US trade deal, when it was an illustrative calculation under the scenario that UK prescription costs went up to US prices.

Flavible projections winning here

Claim: A poll of the City of Durham estimated the Liberal Democrats were ahead.
Rating: False.
Reasoning: This year, only Survation and Number Cruncher Politics (which is not a British Polling Council member) have conducted constituency polls. No such poll of the City of Durham constituency has been published.

The bar chart is also not proportional. (Image: Facebook/Lib Dem bar charts are why I have trust issues)

This is, mostly likely, a projection of a national poll onto this constituency. That projection has been falsely described on the election leaflet.

In response to claims they have been using falsely described constituency projections on their literature, a party spokesperson asserted:

Flavible projections are not used on national campaigns. Every time Flavible projections have been used by local campaigns, the source of the data is clear.

On the City of Durham leaflet, the projection’s source is plainly not identified.

Education in aggregate

Claim: The Conservatives are proposing to increase school funding by ‘£14bn over three years’.
Rating: Needs clarification.
Reasoning: The Prime Minister claimed the Conservatives would invest an extra £14bn in schools.

This is accurate, but an atypical way of describing budget increases:

  • £2.6bn in 2020/21;
  • £4.8bn in 2021/22;
  • £7.1bn in 2022/23.

Summed together, that is £14.5bn. However, we normally say the Conservatives are pledging to increase school spending by £7bn, from 2019/20 to 2022/23.

Forecasting gains and losses

Claim: Remaining in the European Union will provide a ‘Remain bonus’ of £50bn. Exiting the EU will cost every person in Scotland £1,600 a year.
Rating: Needs clarification.
Reasoning: Both of these claims from the Liberal Democrat and Scottish National Party leaders, respectively, refer to economic forecasting.

Various forecasts from nearly every economic organisation suggest that the UK will probably grow slower outside the European Union than inside. In HM Treasury analysis published in November 2018, 29 forecasts were compared: only one suggested the UK was expected to have higher economic growth after exiting the European Union.

Jo Swinson, the Liberal Democrat leader, based her claim on analysis by the Institute for Fiscal Studies. The IFS central estimate was that UK GDP would be 1.9% higher in 2024/25 under the scenario of remaining in the EU, compared to leaving.

Deal or No Deal. (Source: IFS/Citi)

This estimate is then translated into increases in tax receipts, and includes the increased fiscal transfer to the European Union. Paul Johnson, the IFS Director, says this figure is subject to “a huge amount of uncertainty”.

In a campaign speech, Nicola Sturgeon, SNP leader and Scotland’s First Minister, claimed:

Economic analysis says that it will cost every person in Scotland £1,600.

The Scottish government’s analysis in January 2018 estimated that Scottish GDP per person would be £1,600 lower in 2030 — but this is not the same as personal income. The impact on personal incomes would be considerably smaller. The £1,600 figure results from their central estimate of Scottish GDP being 6.1% lower compared to remaining in the EU, in 2030.

This analysis is again subject to huge uncertainty, especially it was published prior to any withdrawal agreements being reached with the European Union.

A similar issue arose during the 2016 EU referendum, with the Britain Stronger in Europe campaign claiming exiting the EU would cost every household £4,300. As the Treasury Select Committee report in 2016 stated:

The Treasury’s analysis contains a foreword from the Chancellor suggesting that “families would be £4,300 worse off” as a result of Brexit. But this is not what the main Treasury analysis found; the average impact on household disposable incomes would be considerably smaller than this number, which refers to the impact on GDP per household.

This blog looks at the use of statistics in Britain and beyond. It is written by RSS Statistical Ambassador and Chartered Statistician @anthonybmasters.

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