Feeds

DfT 'unwittingly' bigged-up speed camera benefits

Rumours of their awesomeness exaggerated, dept admits to Reg

Remote control for virtualized desktops

Exclusive The Department for Transport (DfT) has "unwittingly" misled the public over the benefits of speed cameras for the last four years.

That was the shock admission yesterday by a DfT spokeswoman, when finally cornered by the Department’s own research. She also told us that they have finally agreed to put matters right by adding an explanation to future public statements.

The misinformation began with a report produced by the DfT (pdf) itself in 2005. On the basis of this report, it came up with the now infamous claim that speed cameras are directly responsible for reducing the level of killed and seriously injured (KSI) at camera sites by 42 per cent. Yet its own evidence barely supported half that figure.

The claim has been repeated frequently by official spokespersons and road safety campaigners, and on the DfT’s own Think! road safety website. It has also been regularly questioned by speed camera opponents, who point out that other effects should be taken into account. These include overall "trend" improvements in the KSI rate, other road safety measures put in place at accident black spots, and a statistical quirk known as "regression to the mean".

That last factor is important. Scientists and statisticians have long been aware that whenever something out of the ordinary happens – from a plague of frogs to a spate of road accidents - it is probably just that: a freak, a fluke, an anomaly. Anything that you do in that location after the event will look as though it makes a difference – but it hasn’t. The figures would have returned to a more normal average rate of their own accord anyway.

When the DfT first started claiming such a high benefit for speed cameras, respected academics Dr Linda Mountain of Liverpool University and Mike Maher, Professor of the Mathematical Analysis of Transport Systems at Leeds, objected. The DfT took notice, and the 2005 report included an appendix supplied by this pair showing in meticulous detail how the effect of speed cameras was almost certainly less than half the 42 per cent quoted.

The Reg has raised this with the Department for Transport many times since. On each occasion we have been fobbed off. In one instance, a spokesman told us that statistical analysis was no more than "a matter of opinion".

So far, so stonewalled - until this week, when the DfT decided that speed cams were no longer quite so deserving of central government support. Once more we drew their attention to this issue, expecting to be brushed off again. At long last, a spokeswoman told us: "This was basically an oversight and it will be corrected."

We checked: she confirmed. In future, DfT websites will still contain the 42 per cent claim, but there will be further explanation – or so we have now been assured.

A quick check of the Think! site shows the figure has already been changed. ®

Beginner's guide to SSL certificates

More from The Register

next story
Bladerunner sequel might actually be good. Harrison Ford is in it
Go ahead, you're all clear, kid... Sorry, wrong film
Euro Parliament VOTES to BREAK UP GOOGLE. Er, OK then
It CANNA do it, captain.They DON'T have the POWER!
Musicians sue UK.gov over 'zero pay' copyright fix
Everyone else in Europe compensates us - why can't you?
I'll be back (and forward): Hollywood's time travel tribulations
Quick, call the Time Cops to sort out this paradox!
Megaupload overlord Kim Dotcom: The US HAS RADICALISED ME!
Now my lawyers have bailed 'cos I'm 'OFFICIALLY' BROKE
Forget Hillary, HP's ex CARLY FIORINA 'wants to be next US Prez'
Former CEO has political ambitions again, according to Washington DC sources
prev story

Whitepapers

10 ways wire data helps conquer IT complexity
IT teams can automatically detect problems across the IT environment, spot data theft, select unique pieces of transaction payloads to send to a data source, and more.
Getting started with customer-focused identity management
Learn why identity is a fundamental requirement to digital growth, and how without it there is no way to identify and engage customers in a meaningful way.
How to determine if cloud backup is right for your servers
Two key factors, technical feasibility and TCO economics, that backup and IT operations managers should consider when assessing cloud backup.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.
Mitigating web security risk with SSL certificates
Web-based systems are essential tools for running business processes and delivering services to customers.