General Election 2019 Stat Checks: Week Four

Questionable use of statistics and claims continued in the fourth week.

The fourth week of formal campaigning for the General Election 2019 concluded. There were various claims made by the parties and campaigners.

Tower of assumptions

Claim: Labour are proposing to tax a person with £80,000 earned income a total of £78,000.
Rating: False.
Reasoning: Ryan Bourne (Cato Institute) divided £80bn in proposed new tax revenue by 1.5m (the number of income taxpayers in the top 5%) to yield £53,000. A mean average is inappropriate here, as the income distribution is ‘right-skewed’ — few people have high incomes.

It is based on a false claim made by Labour: their manifesto involves higher direct taxes on people with incomes under £80,000 (removal of the marriage tax allowance; capital gains and dividends taxed at income tax rates).

A Conservative campaigner then applied this £53,000 figure flatly to a person with £80,000 earned income, adding to their claimed extant £25,000 taxes. This is false — income taxes are paid marginally: only income above the threshold has the rate applied.

National insurance contributions are also applied, and considered part of direct taxation.

Image for post
Image for post
This is an illustration of marginal income taxation. In the UK, National Insurance is also paid. (Image: Mona Chalabi)

The results of Warrington South

Claim: From previous elections, voting for “anyone other than the Liberal Democrats can end up with a Labour MP” in Warrington South.
Rating: False.
Reasoning: This claim was made as part of a Liberal Democrat letter from Mike Smithson.

The 2017 General Election results for that constituency were:

Image for post
Image for post
That does not look like a Labour-Liberal Democrat marginal seat. (Image: BBC)

In the past two elections, the Liberal Democrats have had under 6% of the vote. The constituency has only had a Labour or Conservative MP since its creation in 1983.

50,000 nurses

Claim: A Conservative government would deliver 50,000 more nurses.
Rating: Needs clarification.
Reasoning: As part of the Conservative manifesto, the party is pledging “50,000 more nurses”.

Image for post
Image for post
In 2009, there was a methodology change so numbers not directly comparable. (Image: BBC)

Various reports have identified that around 19,000 of those nurses would be ‘retained’ — that is, these are nurses who are already working for the NHS. There is some confusion over whether this pledge to be achieved by five years or in ten years. The Health Secretary defended this figure on Good Morning Britain:

By reducing the number who leave, you increase the number who are there, so 50,000 more nurses.

There needs to be some clarification over what the Conservatives are proposing with this pledge: will the total nursing level (in Full-Time Equivalent terms) be 31,000 or 50,000 higher than it is the latest year, and by what year?

Cash increase for the NHS

Claim: The Conservatives are proposing an extra £33.9bn spending for the NHS.
Rating: Needs clarification.
Reasoning: In a letter from the Prime Minister to my household, Johnson wrote:

£33.9 billion for the NHS.

As is made clear in other places, such as the Conservative costings document, this figure is a ‘cash increase’ — not adjusted for inflation.

As Full Fact have identified, the real terms increase (that is, adjusted for inflation) is £20.5bn from 2018/19 to 2023/24. This is the largest such increase since the mid-2000s.

Image for post
Image for post
There have been changes in accounting practices, leading to discontinuities. (Image: Full Fact)

It is likely to be misleading to state this is the ‘largest cash boost’ in the history of the NHS (which has been made elsewhere, but not in the letter).

‘Sky projected 395 Conservative seats’

Claim: Sky News projected the Conservatives to win 395 seats in the 2017 General Election.
Rating: Likely to be misleading.
Reasoning: The account for ‘PollsdotUK’ wrote:

SkyNews 2017 Projection for Westminster. Conservatives 395 seats?? And it is our polling that is dubious?

The included image is from a Sky projection, based on YouGov polling conducted on 12–13th April 2017.

The central estimate was a 21 point Conservative lead. Plainly, there was a large change in public opinion after then. ‘PollsdotUK’ has most recently claimed to have conducted 1,045 face-to-face interviews in Hull West & Hessle in one day.

MRP estimates are not constituency polls

Claim: The Labour candidate for Kensington said “LABOUR POLLING AHEAD IN KENSINGTON!”.
Rating: False.
Reasoning: Emma Dent Coad, the Labour candidate for Kensington, wrote on Twitter:

MRP estimates are not constituency polls. Multi-level regression with post-stratification is a statistical technique to build a model of individual public opinion, which can vary by constituency.

There is a lot of uncertainty. Even when built from the same technique, different models can provide different estimates for each constituency. For instance, the Blumenau-Lauderdale model (produced for YouGov) centrally estimates Labour are third in Kensington — but the race is a three-way marginal between the Conservatives Labour, and the Liberal Democrats.

Image for post
Image for post
This is going to be a close one. (Image: YouGov/UCL)

Also, there was a constituency poll of Kensington. Deltapoll interviewed 500 electors in Kensington by telephone between 7–13 November 2019. This telephony poll also estimated Labour were third on 27%.

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

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store