Wilson's School Maths: 2012

Monday 16 July 2012

What is the significance of 56,075,900?

The government has started releasing data from last years census. According to this the population of Engalnd and Wales has reached 56.1 million (there official estimate is 56,075,900) up 3.7 million on a decade earlier.

Residents in England and Wales from 1801 -2011

The census also reveals our ageing population.

Population by age and sex, 2001 and 2011, England and Wales

Source - http://www.ons.gov.uk/ons/dcp171778_270487.pdf

Look out for more census news over the summer. We will be back with the blog in September.

Tuesday 3 July 2012

Wimbledon: the statistics behind winning

Euro 2012

It may not surprise you that Spain made the most passes at Euro 2012.

But which team made the most saves? The answer may suprise you!

See the answer and all the Euro 2012 data you could possibly want at:

http://www.guardian.co.uk/football/datablog/2012/jul/02/euro-2012-statistics-opta-data

Sunday 20 May 2012

How Facebook became the world's biggest social network - animation

Facebook is hitting the stock exchange with its IPO later this week - and the latest estimates increase its potential valuation, making it the biggest floatation ever. But how did the social network get so big - and can it possibly get any bigger?

Source - the guardian

Wednesday 2 May 2012

The wettest drought ever

April was the wettest on record with Engalnd receiving 75% more rain than it does on average. Yet we remain in drought!

This graph which shows the percentage above or below the average level of rainfall for each month since the start of 2010 shows why one wet month may not solve the problem.

Source - http://www.bbc.co.uk/weather/feeds/17903057

Tuesday 1 May 2012

Black-Scholes: The maths formula linked to the financial crash

BBC News Magazine recently featured a formula that is apparently related to the financial crash - the Black-Scholes model.

$C(S,t)=N(d_1)~S-N(d_2)~K e^{-r(T-t)}\,$
$d_1=\frac{\ln(\frac{S}{K})+(r+\frac{\sigma^{2}}{2})(T-t)}{\sigma\sqrt{T-t}}$
$d_2=\frac{\ln(\frac{S}{K})+(r-\frac{\sigma^{2}}{2})(T-t)}{\sigma\sqrt{T-t}} = d_{1}-\sigma\sqrt{T-t}.$

$\begin{align} P(S,t) &= Ke^{-r(T-t)}-S+C(S,t)\\ &= N(-d_{2})~K e^{-r(T-t)}-N(-d_{1})~S. \end{align}\,$

See the Wikipedia article for details. A-level students will notice the following:

it's multivariable
it's got exponentials
it's got logarithms
it's hard!

Here is an excerpt from the BBC article:

Black-Scholes was first written down in the early 1970s but its story starts earlier than that, in the Dojima Rice Exchange in 17th Century Japan where futures contracts were written for rice traders. A simple futures contract says that I will agree to buy rice from you in one year's time, at a price that we agree right now.

By the 20th Century the Chicago Board of Trade was providing a marketplace for traders to deal not only in futures but in options contracts. An example of an option is a contract where we agree that I can buy rice from you at any time over the next year, at a price that we agree right now - but I don't have to if I don't want to.

Options allow a trader to have a delicious risk-free portfolio You can imagine why this kind of contract might be useful. If I am running a big chain of hamburger restaurants, but I don't know how much beef I'll need to buy next year, and I am nervous that the price of beef might rise, well - all I need is to buy some options on beef.

But then that leads to a very ticklish problem. How much should I be paying for those beef options? What are they worth? And that's where this world-changing equation, the Black-Scholes formula, can help.

from http://www.bbc.co.uk/news/magazine-17866646

Sunday 22 April 2012

Species Extinction

The Convention on Biological Diversity claims that up to 150 species of animals and plants become extinct each day. Yet the International Union for the Conservation of Nature only has a list of 801 species that have been lost in the last 500 years.

A great piece on this weeks More or Less explains why questions such as counting how many species are going extinct (or even how many species there are) can prove very difficult to come up with even vaguely accurate answers to.

Source - http://www.bbc.co.uk/programmes/b006qshd

Sunday 25 March 2012

More or Less

On the right hand side of the page I've added an RSS feed for the More or Less Podcast; this should automatically update with the latest versions of the program.

Each week Tim Hartford explains - and sometimes debunks - the numbers and statistics used in political debate, the news and everyday life.

This week what is the world average salary?

Thursday 22 March 2012

The Budget 2012

Statisticians and economists have had a field day in interpreting this year's Budget. It is difficult to find an unbiased report on George Osborne's offerings this year, but Channel 4 News Factcheck does a credible job in trying to answer the question, who really are the winners and losers?

Will the wealthiest pay more or less?

The blog nicely sums up how difficult it is to model people's behaviour with respect to tax avoidance: "all academics stress that these numbers are vague and forecasts can easily be wrong."

Sunday 18 March 2012

Misleading statistics about eating red meat

Statistics gone wrong? In response to recent research from Harvard School of Public Health about the health risks of eating red meat, Channel 4 News' Cathy Newman interviewed a St. George's Hospital dietician - who says that the statistics are misleading. Watch the interview here.

Tuesday 13 March 2012

What data can reveal about someones life

Stephen Wolfram (the founder of Wolfram Alpha) has published some interesting data that gives a revealing portrait of his own life.

Amongst other things he has recorded the time of every one of the 300,000 e-mails that he has sent in the last 20 years:

Not only can you get a clear view of his work day but also the increase in the use of e-mail in that time. This is revealed in more detail here with clear peaks as the big projects he has worked on have come to fruition:

Not only has he looked at e-mail but he has also recorded other information about himself such as the number of paces he takes each day, and even the number of key strokes on his keyboard. Putting this together:

Source - http://blog.stephenwolfram.com/2012/03/the-personal-analytics-of-my-life/

Tuesday 6 March 2012

Graduate employment

New data shows that:

More graduates are employed in lower skill jobs.

1 in 5 graduates are unemployed.

Medicine and dentistry graduates remain the best paid, closely followed by maths and engineering graduates.

Source - http://www.guardian.co.uk/news/datablog/2012/mar/06/graduate-employment-low-skill-jobs

Sunday 4 March 2012

Study statistics

According to Hal Varian from google:

"the sexy job in the next ten years will be statisticians. People think I'm joking, but who would've guessed that computer engineers would've been the sexy job of the 1990s?"

A new report estimates that the US alone will need an extra 1.5 million managers capable of making decisions based on data.

Friday 10 February 2012

Oxford University Press Maths Photography Competition 2012

Win an ipad 2!
For details see http://www.oup.com/oxed/secondary/mathsphotocomp/
The final closing date for all entries is 16th March 2012. Hand in entries to Miss Mauthoor.

Saturday 4 February 2012

European Super Highway of Debt

Wondering just how big the Euro debt crisis is? These frightening infographics show you using lorries packed with €100 notes...

Source: http://demonocracy.info/infographics/eu/debt_piigs/debt_piigs.htm

Wednesday 1 February 2012

February competition - correlation or causation?

Need to 'prove' something you already believe?
It's easy with statistics! All you need are two graphs and a leading question.

Source - http://www.businessweek.com/magazine/correlation-or-causation-12012011-gfx.html

The competition

Make your own misleading graph that shows correlation and implies causation (even if there is no basis for doing so).
Open to all years, all entries to be given to Mr Alderson by midday, Wednesday 29th February.

Monday 30 January 2012

Stephen Hester's bonus

What else could you buy with a bank chief's bonus? What is Stephen Hester worth - visualised. What is Stephen Hester worth?

Source - http://www.guardian.co.uk/news/datablog/graphic/2012/jan/28/stephen-hester-bonus-graphic

Wednesday 25 January 2012

Economics - UK recessions compared

The latest GDP figures released today showed that the UK economy shrank by 0.2% in the last quarter of 2011. How does this recession compare to previous ones?

National Institute of Economic and Social Research