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I’ve had a lot of publicity over the last few days, but none of it was welcome. It arose from the story below from the Daily Telegraph of June 6 with the headline “Britons are having less sex, and Game of Thrones could be to blame, says Cambridge professor”

Yesterday the Chief Medical Officer announced new guidelines for alcohol consumption. The Summary says,

The proposed guidelines and the expert group report that underpins them, have been developed on the basis of the following principles:

The way that risks are 'framed' can make a big impression on their apparent magnitude. The controversy following the recent report by NICE on hormone replacement therapy (HRT) provides a fine example.

I like doing live interviews for radio or TV – it’s exciting and they can’t edit what you say. The programme is almost inevitably running late, so last Saturday morning when I did an interview for Radio 4’s Today I remembered my media training and had prepared carefully to get my points over before they cut me off.

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”.

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?

A story in monday's Times had the following dramatic headline:

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.

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.

Yesterday the Sunday Times [paywall] covered a talk Anne Johnson and I had given at the Cheltenham Science Festival about the statistics of sex, and the article said

more people are having sex in their teens, roughly 30% before the age of 16.

Yesterday the Daily Mail trumpeted “For every hour of screen time, the risk of family life being disrupted and children having poorer emotional wellbeing may be doubled”, while the Daily Telegraph said that "for every hour each day a child spent in front of a screen, the chance of becoming depressed, anxious or being bullied rose by up to 100 per cent”.

More or Less recently featured Jody Aberdein talking about the cluster of 6 cycle deaths in London over a 2 week period.

The paper with the details of the analysis can, for a while, be freely obtained from Significance magazine.

What a strange organisation the Press Complaints Commission (PCC) is. They say that a press article is inaccurate, but consider it reasonable that the inaccurate headline remains uncorrected.

Following the consultation discussed previously on this blog, the Department for Education has announced the revised content for GCSE Mathematics.

Compared to the current content, the most notable changes are (a) separation of probability and statistics, (b) removal of the data-cycle, (c) increased material.

The proposed content for probability is as follows:

When on holiday at Whitby we took this photo of this extraordinary memorial to Mr and Mrs Huntrodds.

I was very saddened by the death on Friday of a Boris-bike rider in Whitechapel High Street, particularly as I am a frequent and enthusiastic user of the scheme. But as a statistician, I also immediately wondered how surprised I should be about the fact that this was the first fatality of the bikes.

The Daily Mail headline below is unequivocal – statins cause a 20% increase in muscle problems.

There is reasonable public outrage at possible criminal conspiracies to adulterate meat products with horsemeat, and additional concerns raised about the presence of the anti-inflammatory known as bute.

Some of the coverage of yesterday's story about drinking in pregnancy and IQ of children was not entirely accurate. The Times reported that 'women who drink even a couple of glasses of wine a week during pregnancy are risking a two-point drop in their child's IQ', and 'children whose mothers drank between 1 and 6 units a week - up to three large glasses of wine - had IQs about two points lower '(than mothers who did not drink).

As in ‘Boffins jailed for not predicting earthquake’, the 6-year sentences and massive fines handed out to the Italian seismologists have been largely portrayed by the media and commentators outside Italy as an attack on science, and the prosecution ridiculed as expecting the scientists to have been able to predict the earthquake.

These guidelines were submitted by the Science Media Centre to the Leveson Inquiry into the press.

Announcements about the Higgs Boson are invariably framed in terms of the number of sigmas, with 5-sigmas needed for a ‘discovery’. Media outlets helpfully explain what this means by translating 5-sigmas to a probability, which is almost invariably misreported as a probability of the hypothesis that it is all just statistical error e.g.

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.

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?

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?

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.

The BBC News website and Radio 4 news both led this morning on the Royal College of Surgeons' report on emergency surgery. The BBC web site states that
'A report by the college highlights figures that show that about 170,000 patients undergo emergency abdominal operations each year. Of these, 100,000 will develop complications and 25,000 of these patients will die.'

(appeared in the Times, 26th September 2011) - pdf here

Now that the rogue US satellite has crashed into the Pacific we can all come out from under our beds. The biggest bit of the satellite was about the weight of an adult gorilla, although not as soft, and travelled at 100 mph so it sounds rather ominous, but people only take up one 80,000th of the earth’s surface so it would be more than an unlucky day if anyone had been hit. 40 tons of debris got scattered over mainland USA after the Columbia shuttle disaster and nobody was injured, although NASA afterwards concluded there had been around a 1 in 4 chance of some casualties.

The Daily Mail and other media sources have featured league tables for the 'luckiest parts of the country' based on the proportion of the population that have become millionaires by winning the lottery. Straight Statistics have done a nice demolition job on this absurd story, pointing out that any comparison should be based on the number of tickets sold, not the population.

A report claiming that users of the Internet Explorer browser had lower IQs than users of other browsers has been revealed to be a hoax. I had been asked to comment on the report by BBC Technology and had got suspicious about the figures. The perpetrators of the hoax, which had received extensive coverage, have listed the reasons why they should have been detected, but did not include 'dubious statistics' in their list.

If mobile phones don't cause brain tumours, what does? Well, according to stories today in the Daily Mail and the Daily Telegraph, it might be cats. Or at any rate a parasite called Toxoplasma gondii, one of whose hosts is the domestic cat. But don't go exiling your kitties yet; the admirable Ed Yong has explained in his blog that the study in question doesn't establish anything of the sort.

World cup fever is again gripping the globe - well, perhaps not so strongly as last time, but the Women's World Cup football finals are about to begin in Germany. And as the excitement builds, the aquarium chain that brought us Paul the "psychic" octopus is rising to the new challenge. Paul himself has ascended to the great aquarium in the sky, so the search is on for a worthy successor

When it comes to causing cancer in humans, is using a mobile phone as risky as talcum powder, or as risky as coffee, or as risky as the notorious insecticide DDT? Actually we don't know, as I explained in my previous blog entry on last week's IARC announcement on mobile phones and brain cancer. That didn't stop the media comparing the risk of mobile phone use with all these things and more. But why did different newspapers make different comparisons?

In our article on ESP and the significance of significance, I made a prediction on the controversy surrounding psychologist Daryl Bem's paper "Feeling the Future" - the one that claimed to find evidence for some forms of ESP (extra-sensory perception). "This one will run and run", I boldly prophesied. And so it came to pass.

The UK news media have reported quite extensively a newly published paper by Wald, Simmonds and Morris on screening for cardiovascular disease (CVD) - that is, disease of the heart and blood vessels (principally heart attacks and strokes). The paper concluded that screening should be based on the patient's age alone, and not on other risk factors for CVD. But I'm not going to examine the conclusion - I'm interested in the way the authors dealt with uncertainty.

The New York Times has published an excellent (well, I thought so) article called Do Cellphones Cause Brain Cancer?. What's particularly good about it is the clear but thorough way that it explains the problems of looking for causes of rare diseases, and describes the methods used for dealing with uncertainty in this challenging context.

The recent study on alcohol and cancer published in the British Medical Journal is a fine piece of epidemiology and attracted a lot of coverage of the estimate that 10% of male cancers and 3% of female cancers could be attributed to alcohol. But while it is useful as a description of what happens in populations, as usual when translated to an individual it stops looking so impressive.

Statistical significance testing is a pretty tricky concept. We're planning to post an article on it soon, but until we get round to it, here's a link to something excellent on the topic from the xkcd Web comic. They're illustrating exactly what people misunderstand. Maybe we needn't bother with the article after all...

Most school textbooks contain messages about health. But there's no known evidence for about a quarter of the messages. At least, that's the position in Granada, Spain, according to a report in BMC Public Health.

Google seems to be doing pretty well everything these days. Their UK operation has just published the first issue of a new magazine, Think Quarterly, and it's all about data. It looks very pleasant, particularly if you read the version that emulates a print magazine. And there's some interesting content, including interviews with Hans Rosling and with Hal Varian, Google's Chief Economist who famously said in 2009 that "the sexy job in the next 10 years will be statisticians." But, strangely, the whole magazine says nothing explicit about uncertainty.

This article on the perception of the risks of radiation appeared on the BBC News website: here is the original version with more links and corrections.

Did an article in the Times [paywall] today on the forthcoming EU Court of Justice ruling on whether gender can be taken into account when setting insurance premiums. I think this is an important and interesting topic, but articles in the financial pages have been very dull and so tried to make this a bit lighter in tone. Text of article is here.

Are we all drowning in a deluge of data? Are our data tools and systems managing to keep up with all the numbers we're collecting all the time? A series of articles in the journal Science doesn't give an entirely positive view, at least in terms of what's going on in the scientific research community. But what does that have to do with uncertainty?

New online crime maps for England and Wales have just been published. They seem to show numbers of crimes for single streets. If you're in England or Wales, you'll probably have seen all the fuss about them in the media. But what do they actually tell us about the risks of crime?

The Sun today features a story about a family who have had three children all born at 7.43 (two am and one pm). Heartwarming, but the quoted odds of 300,000,000 to one are sadly wrong.

We've previously shown that the number of homicides each day in London followed a Poisson distribution to a remarkable degree - this means that they essentially occur as a random process. Now the same analysis has been repeated by the Home Office in the crime statistics released today - and the Poisson fits very well.

Assiduous readers of understandinguncertainty.org will know that we often refer to odds. Pretty well everyone will have heard of odds, and will at least know that they have something to do with how likely something is to happen. But beyond that, it can get trickier, as an entry in a blog about language has reminded us.

For the last few weeks, Chris Maslanka's excellent maths puzzle column in the Guardian has been running variants on the following problem. Fred and Sam play a game in which the winner is the first to flip a head. They take it in turns, Fred starting. What's the chance that Fred wins? I have been asking this to 6th form audiences and the general response is 2/3 or 3/4, but nobody can say why. Here is the solution I have been using.

I got a commentary in the Times today (due to the Times paywall, this is a local link to the unedited article, rather than to the published version) about a study that estimated that people rated as 'unattractive' when they were 7 years old only had 44% chance of their first child being a girl. This effect seems utterly implausible.

Got an article in the Times about the Walkers Crisps forecasting competition. Since then have won another £10. Shame the paywall means there is no point in linking to the online version.

I have just won £10 in the Walker's Crisps Rainy Day promotion. Each packet of crisps has a code that allows you to choose a 2km x 2km square in the UK or Republic of Ireland in which you think it will rain in a couple of days time. I won after only three entries at a crisp cost of £1.20, which seems quite a good deal.

We are working with the Met Office on a project comparing alternative ways of presenting uncertainty about short-term weather forecasts, and have a 6-month internship available for a PhD student. See this link for details.

A recent study showed no evidence of an adverse effect of moderate consumption of alcohol during pregnancy and subsequent child development. But the Department of Health has commented "After assessing the available evidence, we cannot say with confidence that drinking during pregnancy is safe and will not harm your baby. Therefore, as a precautionary measure, our advice to pregnant women and women trying to conceive is to avoid alcohol."
Is this still a tenable position?

The Inter-Academy Council (IAC) recently produced a report on the workings of the Intergovernmental Panel for Climate Change (IPCC) which got a lot of publicity, but almost no coverage was given to what the IAC said about the IPCC's way of handling uncertainty. It makes interesting reading.

This is an article that appeared in the Times on Friday July 2nd - sadly everyone now has to pay to access Times articles online.

Who is exposed to the greater lethal risk: a member of the UK forces serving in Afghanistan, or an average patient spending the night in an English hospital? Of course the question can’t be answered exactly: it all depends on who we mean and how we measure risk. But statistics can give us a ball-park figure that may be surprising.

Do you reckon you have good statistical skills? Now's the chance to prove it in two forecasting competitions that are running this month, both of which feature the Eurovision Song Contest.

In the first televised election debate last Thursday, David Cameron stated that “I have a man in my constituency … who had kidney cancer who came to see me with seven others. Tragically, two of them have died because they couldn't get the drug Sutent that they wanted..”. How reasonable was it to claim that two would not have died had they had access to Sutent? Some statistical analysis can give us an insight.

Do you think that kids are being over-protected and need more risk in their lives? If so, you may be surprised to find that the Chair of the Health and Safety Executive (HSE) and the Chief Executive of the Royal Society for the Prevention of Accidents (RoSPA) agree with you.

The English Outdoor Council has just released a fine report by Tim Gill,
"Nothing ventured: balancing risks and benefits in the outdoors" which "explodes the myths about safety on school visits and gives real reassurance to teachers"

I was lucky enough to get included in the Horizon programme on Infinity last night, talking about the old monkey-Shakespeare issue. Of course most of my rambling contribution was (rightly) cut, so here’s a few background details for anyone interested.

Elsewhere on this site we talk about the difficulties in making reliable rankings of footbal teams, but at least people can agree that winning matches is a reasonable way to measure the quality of a team. Hospitals are different - even something 'obvious' such as mortality statistics may not be the best way to asses patient safety. This is an article that appeared in the Times on December 2nd, with suitable links added.