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GPUs, Monte Carlo Simulation and Kooderive with Mark Joshi - February 25-27th Mathfinance Conference 2015

Understanding Uncertainty's Blog


The risk of queuing?

November 8, 2011 Comments (0)

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 excellentHome 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...

Another doubtful league table?

November 1, 2011 Comments (0)

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? The league tables are available here but only give percentages. Considerable searching is necessary to find the raw numbers on which these percentages are based, but it is possible to eventually discover...

A probability paradox?

October 31, 2011 Comments (0)

I recently tweeted a link to this problem drawn on a blackboard, which got a lot of retweets. Multiple Choice: If you choose an answer to this question at random, what is the chance you will be correct? A) 25% B) 50% C) 60% D) 25% This is a fun question whose paradoxical, self-referential nature quickly reveals itself – A) seems to be fine until one realizes the D) option is also 25%. A quick search reveals hundreds of discussion contributions of this problem, for example here and here and from...

A Maserati for £1

October 17, 2011 Comments (0)

After Dave and Angela Dawes won £101 million on the Euromillions lottery, Radio 5 Live asked me to comment on the different ways one could win a decent amount of money for £1. I chose £100,000, which will buy you a shiny new Maserati ( a Ferrari would be about double that). The recording of my interview is here, and here are the details of my calculations, which I hope are roughly correct. National Lottery There are 49 balls and if your choice of 6 numbers matches 5 winning balls plus the...

Surgeons create Frankenstein numbers?

September 29, 2011 Comments (0)

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.' The actual RCS report, on the other hand, says that ‘In the UK, 170,000 patients undergo higher risk non-cardiac surgery each...

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....