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MoneyScience Financial Training: Introduction to QuantLib Development with Luigi Ballabio - September 22-24, London, UK - Further Information
GPUs, Monte Carlo Simulation and Kooderive with Professor Mark Joshi - October 29-31, London, UK - Further Information

Understanding Uncertainty's Blog

 

Divide and rule: getting rates in a mess

September 28, 2011 Comments (0)

I've been a bit inactive in here for a few weeks, because I've temporarily moved to Berlin. But it turns out that one can find bad presentations of risk in the German media too, and here's one, pointed out to me by my new colleague Jan Multmeier. The topic is a rather serious one: suicide rates in German troops serving abroad, and the error involves dividing by the wrong thing when calculating rates. This featured in an article on the website of the main German TV evening news programme, where...

The dangers of 'don't worry'

September 27, 2011 Comments (0)

(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...

Get under the table?

September 23, 2011 Comments (0)

The remnants of the Upper Atmosphere Research Satellite (UARS) are due to hit the earth later today and NASA have put up some details of their risk assessment. But this doesn't say where their '1 in 3200 chance of anyone being hit' comes from, and so can we get this figure from a back-of-an-envelope calculation? The satellite has been up 20 years, stopped working in 2005, and weighs 5700 kg, about the size and weight of a double-decker bus. NASA say it will break into 26 objects that will...

Lottery league tables

September 15, 2011 Comments (0)

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. The Daily Mail showed the league table below, and trumpeted that the North East was the luckiest region and Northern...

Visualising uncertainty about the future

September 12, 2011 Comments (0)

A great use of a 'spaghetti plot' of multiple model predictions for Hurricane Katia . This seems to communicate essential unpredictability well through the metaphor of 'multiple possible futures', even though what is being portrayed is between-model disagreement rather than within-model uncertainty. We have just had a review paper published in Science called Visualising uncertainty about the future, although it primarily focuses on probability forecasts. Sadly it's sitting behind a paywall....

Japan nuclear threat: The tsunami is the bigger tragedy

August 25, 2011 Comments (0)

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. The apocalyptic visions of destruction brought by the Japanese earthquake and subsequent tsunami have been largely replaced in the media by reports of the struggle to control radiation from the stricken Fukushima nuclear plant. This provides a gripping narrative – a brave team battling to contain the threat, warnings of catastrophe and claims...

"Official": it does matter how risk statistics are presented

August 25, 2011 Comments (0)

The respected and influential Cochrane Collaboration has just published a systematic review of research on different ways of presenting risks and reductions in risk in a health context. It won't come as a surprise to regular readers of this website that they concluded that some aspects of the presentation really do make a difference. But maybe there are a few surprises in their detailed findings. The Cochrane Collaboration is an independent international organisation that prepares and publishes...

Car insurance? How big are your feet?

August 25, 2011 Comments (0)

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. Free tags: insuranceLevels: level 1

Odd odds

August 25, 2011 Comments (0)

Ben McGarry pointed out this blog entry about an article published in Sexually Transmitted Infections Online that says some rather odd things. The article says that men sent text messages to remind them to have HIV tests had double the testing rate compared to men not sent messages, and after statistical adjustment for difference between the groups "re-testing was 4.4 times more likely". But since the testing rate was 30% in the group not sent text messages, how could testing be 4 times more...

Daily Mail gets odds right shock

August 25, 2011 Comments (0)

The Daily Mail and other papers carried the story about the Banwell family whose third child shares a birthday, February 5th, with two older siblings, and this time they got the odds right at 133,000 to 1! This example on February 5th was preceded by the Allali family on October 7th 2010, where the Mail got the odds wrong, and the MacKriell family on January 29th 2008 where they got the odds right - see our previous blog. As Ben Goldacre has discussed, around 167,000 third or higher...