Welcome to Understanding Uncertainty

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.


/sex-numbers

Sex by Numbers, by David Spiegelhalter, is now available for purchase!

Details of reviews, interviews, (and errors) are all featured here.


Do you have a coincidence story? David Spiegelhalter is collecting them over at http://cambridgecoincidences.org.


Elsewhere on UnderstandingUncertainty:

Sensationalist promotion by the World Cancer Research Fund

Today the Daily Telegraph featured the powerful headline "Just three alcoholic drinks a day can cause liver cancer, warns new study" , based on a press release from the World Cancer Research Fund headed “Three alcoholic drinks a day can cause liver cancer, new research finds”.

Misleading conclusions from alcohol protection study

The Daily Mail today declared that "Drinking is only good for you if you are a woman over 65", while the Times trumpeted that "Alcohol has no health benefits after all".

But these headlines are without serious foundation, and through no fault of the journalists.

How many hours of life did Obama lose in Delhi?

obama-delhi.png

President Barack Obama recently spent 3 days in Delhi, and it’s been claimed that during this period the air pollution knocked 6 hours off his life. So who was responsible for this number?

Luck and Cancer

I was on Radio 4 PM (starting at 37:09) and BBC News Channel yesterday discussing the study published in Science " Variation in cancer risk among tissues can be explained by the number of stem cell divisions ". This had been reported by much of the press as showing that “the majority of cancer cases are down to sheer bad luck”.

Sub-editing in the Times

A story in monday's Times had the following dramatic headline:
errors-screening-headline.jpg

Is prostitution really worth £5.7 billion a year?

The EU has demanded rapid payment of £1.7 billion from the UK because our economy has done better than predicted, and some of this is due to the prostitution market now being considered as part of our National Accounts and contributing an extra £5.3 billion to GDP at 2009 prices, which is 0.35% of GDP, half that of agriculture. But is this a reasonable estimate?

Why 'life expectancy' is a misleading summary of survival

It's well-known how misleading it can be to use average (mean) as a summary measure of income: the distribution is very skew, and a few very rich people can hopelessly distort the mean. So median (the value halfway along the distribution) income is generally used, and this might fairly be described as the income of an average person, rather than the average income.

Using expected frequencies when teaching probability

The July 2014 Mathematics Programmes of Study: Key Stage 4 (GCSE) specifies under Probability

{calculate and interpret conditional probabilities through representation using expected frequencies with two-way tables, tree diagrams and Venn diagrams}.

- the brackets and bold case means this comes under additional mathematical content to be taught to more highly attaining pupils.

Another tragic cluster - but how surprised should we be?

Sadly another passenger plane crashed yesterday - the third in 8 days, the Air Algerie flight on July 24th, the TransAsia flight in Taiwan on July 23rd, and Malaysian Airlines in Ukraine on July 17th. Does this mean that flying is becoming more dangerous and we should keep off planes? The following analysis may appear cold-hearted, but is not intended to diminish the impact of this tragic loss on the people and families involved.

Pages

Subscribe to Front page feed