Understanding Uncertainty

Welcome to Understanding Uncertainty

david — Thu, 23 Sep 2010 15:50:00 +0000

Welcome to the site that tries to make sense of chance, risk, luck, uncertainty and probability. Mathematics won't tell us what to do, but we think that understanding the numbers can help us deal with our own uncertainty and allow us to look critically at stories in the media.

Winter Wipeout
Microlives
Doubtful adoption league
Puzzling Chance
A Maserati for £1
Three-fold variation in UK bowel cancer death rates
Lottery league tables
Visualising uncertainty about the future
Cochrane visualisation
Spotting a hoax

Do you have a coincidence story? David Spiegelhalter is collecting them over at http://cambridgecoincidences.org.
We're supporting an exciting schools programme led by Nadia Baker of the Millennium Mathematics Project called What are the Odds? - the Hands on Risk and Probability Show. Follow the link for more information and to find out how to get your school involved.
We guest edited an issue of NRICH recently - a collection of school level problems looking at surprising outcomes.

There will be a lot more things appearing - see About Us.

Meat and dying

david — Wed, 21 Mar 2012 17:50:58 +0000

After all the recent coverage of the possible harms of red meat, I've done an article explaining how, if we believe the figures, eating quite a lot of extra red meat each week will take, on average, a year off our life.

Wiped Out

david — Sat, 17 Dec 2011 11:10:43 +0000

Appearing on Winter Wipeout today. Enough said.

Looking deranged at the prospect of the Big Balls

Wrote an article for the Times, which appeared as this.

BBC website headline wrong shock horror

kevin — Thu, 08 Dec 2011 12:53:49 +0000

Bowel cancer screening 'does cut deaths', said the BBC News website today, in a report on a study using data from the NHS Bowel Cancer Screening Programme in England, published in the magnificently named journal Gut. Wow, I thought, that was quick, the programme has been going only since 2006 and didn't cover the whole country till 2010. Have they really found clear evidence of an effect on death rates already?

Why it’s important to be pedantic about sigmas and commas

david — Sat, 03 Dec 2011 18:59:48 +0000

The BBC reported last week that evidence for the Higgs Boson is “around the two-sigma level of certainty” and provides further explanation:

Particle physics has an accepted definition for a "discovery": a five-sigma level of certainty. The number of standard deviations, or sigmas, is a measure of how unlikely it is that an experimental result is simply down to chance rather than a real effect”

This is nice and clear, but it is also wrong, as we have pointed out before in a previous blog by Kevin McConway.

Are the Brits really fatter than other Europeans?

kevin — Sun, 27 Nov 2011 18:31:20 +0000

Lots of press reports in the last couple of days on how UK women are the fattest in Europe, for example in the Daily Mail and on the BBC News website. I'm still in Berlin, and it was in the papers here too. The tabloid-style Berliner Kurier went with the headline "Man, they are fat, man", while the N24 news service went with "British and Maltese are the fattest Europeans". But is it another dodgy league table?

Microlives

david — Tue, 22 Nov 2011 10:46:30 +0000

Acute risks, such as riding a motorbike or going skydiving, may result in an accident - a natural unit for comparing such risks is the Micromort, which is a 1-in-a-million chance of sudden death, for some defined activity.

The next Piccadilly line train is leaving from ....

david — Sat, 19 Nov 2011 16:24:08 +0000

Kings Cross Station now not only has a platform 9$\frac{3}{4}$, but also a platform 0. And for the numerically challenged, there are repeated announcements that 'customers are advised that Platform 0 is situated next to Platform 1'

I suppose the Underground platforms will now have to be given complex numbers.

The risk of queuing?

david — Tue, 08 Nov 2011 15:29:47 +0000

Got a short article in the Times today about the UK Border Agency relaxing its checks over the summer.

I wish I had included the following interesting information provided by the excellent Home Office Immigration Statistics April-June 2011. In 2010 there were around 100,000,000 admissions to the UK , and around 19,000 non-asylum individuals were refused entry. That's around 1 in 5000 admissions, about 35 plane-loads.

So someone should be able to estimate how many people were admitted who would otherwise have been refused entry - it may not be very many.

Another doubtful league table?

david — Tue, 01 Nov 2011 12:13:58 +0000

David Cameron has prominently commented on the recent performance tables concerning adoption in local authorities, in particular the proportion of children whose adoption placement occurs within 12 months. But are the local authorities really as different as they have been made out to be?