7 February - Thinking about ULEZ, Part 3 - People Will Talk
Another guest post from @tonyofsidcup.
The last paragraph of
my previous post said:
“Well, 59% or 68%, no matter - clearly, majority of Londoners oppose ULEZ, and that’s
why Khan ought to cancel ULEZ!” No, and no. This is actually the key point in the whole
ULEZ consultation business, and one that Fortune and Friends try hardest to avoid. Let’s
hit it on the head in the next post.
This is the next post, and this is the big, two-pronged lie: the average Londoner opposes ULEZ, and Sadiq Khan improperly overruled the public opinion to push through his unpopular policy. In reality,
the average Londoner favours ULEZ - the average Inner Londoner, already within ULEZ so unaffected
by the expansion, favours it, while the average Outer Londoner gives you a different answer
depending on how you ask - so Mayor Khan is going with the public opinion, not against it.
If you watch on YouTube the exchange between Sadiq Khan and Peter Fortune at Mayor’s Question
Time (see Links below), you will hear the mayor repeatedly say: “A consultation is not a referendum”.
To me, it means three things.
First, it is about the decision-maker. With a referendum, the voters decide: before votes are cast,
people agree that the choice with the most votes will be implemented. With a consultation, it is the
body that sponsors the consultation that makes the call. There is no commitment to go with the
most popular choice.
Second, it is about the purpose. A referendum aims to reveal the most popular choice and to
produce a decision. A consultation aims to draw out the arguments “for” and
“against” and to inform a decision. Recall those group emails, the subject of #TheUlezScandal
version 1. 5,000 people saying
“no” in a referendum is 5,000 votes. 5,000 people emailing identical text to consultation organisers is
merely one set of arguments repeated 5,000 times. (If there are any arguments advanced at all).
Third, it is about representativeness. A typical referendum captures a large fraction of the voter
population, and is accepted as representative. If, for example, Bexley Conservatives get 51% of the
votes in the 2022 election - “decisive victory”, according to Teresa O’Neill - we accept that the share
of voting-age Bexleyites favouring Tories is close to 51%. A typical consultation involves a much
smaller fraction of eligible voters, and tends to attract people with strong views (enough motivation
to complete a questionnaire), leaving out the crucial, broad middle. For this reason, “projecting” the
consultation-produced percentages of “ayes” and “noes” on a particular
yes-or-no question to the
entire population is a terrible idea. You want to gauge whole-population “for” and “against”
percentages, but a consultation gives you those for “strongly for” and “strongly against”. The two
sets are completely different, and may point in opposite directions.
(Statisticians talk about “self-selected” surveys, and “self-selection bias”. The
self-selection bias is
distinct from the normal statistical uncertainty, when you estimate “population” quantities based on
a sample. The latter is less of a problem: the wonder of statistics is exactly that you *can* reliably
extrapolate from a sample. The catch is that your sample needs to be representative, or “unbiased”.
A “good” sample of 1,000 people will let you make decent predictions about a population of millions.
A “bad” sample with 100,000 people will be worthless).
With this in mind, let’s have a look at the ULEZ consultation. First, Mayor Khan never promised to
follow the majority opinion. One can accuse Khan of not making “Do you support ULEZ or not?” the
consultation’s question 1, but maybe that’s a difference between a single-question referendum and a
many-questions consultation. A respondent could express their rejection of ULEZ in Question 13 -
“We are proposing to expand the ULEZ London-wide on 29 August 2023. What do you think of the
implementation date?” - by choosing “Should not be implemented”. Discussion of feedback received
through the consultation is presented in AECOM’s report to the mayor and
runs to dozens of pages, with a number of specific ULEZ plan changes linked to that feedback. To
claim that the City Hall dismissed the consultation input would be disingenuous.
Finally, the question of how representative the consultation sample was of London’s population - and
just to clarify, a fair proportion of responses came from outside London - can be answered with a
single chart from that report, showing that 42% of respondents were owners of non-compliant cars from Outer London.
Figuring out this group’s share in London’s population is tricky, but it is abundantly clear that it is not
close to 40% - my guess, based on Bexley data, would be 10-15%. (Note the distinction between
individuals and households, and remember the households without cars). It is accurate to say that
68% of ULEZ consultation respondents opposed ULEZ. It is, however, grossly misleading to say - as
GLA Conservatives did - that 68% of Londoners voted against ULEZ.
To gauge the average Londoner’s stance on ULEZ, you need proper surveys. Only two have been
done, both by YouGov, the market-leading polling agency established by the former chancellor of ill repute Nadhim Zahawi.
The first survey was commissioned by the GLA (i.e. the City Hall, or Khan if you like), ran in July, and repeated the consultation’s Question 13:
We are proposing to expand the ULEZ London-wide on 29 August 2023. What do you think of the implementation date?
● It should be implemented, but at an earlier date
● It should be implemented at the proposed date
● It should be implemented, but at a later date
● It should not be implemented
● Don’t know
The second survey, done in November, was commissioned by GLA Conservatives and had this text:
To generate additional revenue for Transport for London, the Mayor of London is proposing to expand
the Ultra-Low Emission Zone (ULEZ) to a wider area than it currently is. This means non-compliant
vehicles have to pay a £12.50 daily charge for driving within Greater London. Do you think the
Ultra-Low Emission Zone (ULEZ) should or should not be expanded?
● It should be expanded
● It should not be expanded
● Don’t know
The Tory-commissioned survey employs a “leading question”, suggesting a specific motivation for
ULEZ expansion: “to generate revenue”. This is not an honest polling practice, but it is a very effective one, which is why it is used.
The
two polls have produced very different results. In the Tory poll, 51% oppose ULEZ (“Decisive victory!”, says Teresa O’Neill), and 34% support it. In the GLA poll, 51% of Londoners support ULEZ
(“Decisive victory!” says Teresa O’Neill again, looking a little confused), while 27% oppose it. In
essence, you get opposite results. For Outer London only, the GLA poll has 46% “for” against 34%
“against”; the Tory poll has 59% “against” and 29% “for”. The truth is somewhere in between.
Personally, I think that it is closer to the GLA numbers - because the Tory
poll was so manipulatively worded, it should be “down-weighted” - but you may disagree and move the
mark closer to the middle. I think we both will conclude that ULEZ is the winner in Inner London, and in Outer London the split is near 50/50.
So there you have it. GLA Tories’ allegations of #TheULEZScandal are worthless - a ”smokescreen”, as
Sadiq Khan put it, a deception aimed at the vast majority of people with zero interest in learning the
details. The percentage of anti-ULEZ responses to the consultation’s Question 13 was predictable in
advance, and, because of this, irrelevant to the decision-maker, i.e. the mayor. Limited polling
showed support for ULEZ in Inner London, and neutral or moderately anti-ULEZ sentiment
(concentrated among older and less educated voters, already undisposed towards Khan) in Outer
London. Under the circumstances, both an idealist and a cynic would advise the mayor to proceed with his plan, and so he did.
What would a scientist say, though? Never mind the prone-to-manipulation public opinion - is ULEZ
expansion a good idea on public-health grounds? Before we tackle that
million-dollar question, let’s
devote the next, short post to a falsehood that has circulated within the anti-ULEZ discourse and was
recently shared, on the pages of The Telegraph, by one of Sidcup’s finest minds, Gareth Bacon MP.
Links
A good article discussing ULEZ consultation and polls
https://bylinetimes.com/2023/01/23/driver-lobbyist-group-targeting-sadiq-khan-over-clean-air-plans-is-funded-by-road-haulage-industry/
AECOM “Report to Mayor on ULEZ expansion and future Road User Charging proposal” (analysis of consultation responses)
https://haveyoursay.tfl.gov.uk/15619/widgets/58629/documents/34558
ULEZ survey commissioned by GLA, July 2022
https://ehq-production-europe.s3.eu-west-1.amazonaws.com/1756f85d90ec076d413af3d3c7132d9f
ULEZ survey commissioned by GLA Conservatives, November 2022. (Summary only)
https://docs.cdn.yougov.com/n7yjacvt7e/GLAConsResults_221115_LondonULEZ_W.pdf