probability
Actuarial science began as the place where two branches of mathematics meet: compound interest and observed mortality statistics. Financial planning for the future is therefore rooted firmly in the past. John Webb takes us through some of the mathematics involved, introducing us to some of the colourful characters who led the way.
Last October, two mathematicians won £1m when it was revealed that they were the first to solve the Eternity jigsaw puzzle. It had taken them six months and a generous helping of mathematical analysis. Mark Wainwright meets the pair and finds out how they did it.
Evolution is the main theme of this issue. With Darwin's anniversary year not too far off, we find out how to reconstruct the tree of life and how to spot the fingerprint of natural selection. We report on the rapidly melting Arctic, bound to destroy much of evolution's achievements, and explore the maths used in ice and ocean models. And we have a look at cellular automata, simple mathematical models that can evolve surprisingly complex behaviour. Plus you can learn how to best distribute money amongst your employees without evolving envy.
A biologist has developed a blood test for detecting a certain minor abnormality in infants. Obviously if you have blood samples from 100 children, you could find out which children are affected by running 100 separate tests. But mathematicians are never satisfied by the obvious answer. Keith Ball uses information theory to explain how to cut down the number of tests significantly, by pooling samples of blood.
Did you know that you can't average averages? Or that Paris is rainier than London ... but it rains more in London than in Paris? Andrew Stickland explores the dangers that face the unwary when using a single number to summarise complex data.
Collecting chances
"Lies, damned lies, and statistics..." Ben Parker tells us how to tell good statistics from bad, and make sure your cat is well-fed.
Dice are invaluable to many games, especially gambling games, but instead of playing with ordinary 1-6 numbered dice here are two interesting alternatives - with a twist!
According to Darwin, natural selection is the driving force of evolution. It's a beautifully simple idea, but given the thousands of years that are involved, nobody has ever seen it in action. So how can we tell whether or not natural selection occurs and which of our traits are a result of it? In this article Charlotte Mulcare uses milk to show how maths and stats can provide genetic answers.
Life is full of coincidences, but how do you work out if something is really as unlikely as it seems? In this article Rob Eastaway and John Haigh find chance in church and work out the odds.
Why rankings don't work
This issue's teacher package brings together all Plus articles on probability and statistics, exploring anything from maths in the dock to games of chance. It also has some handy links to related problems on our sister site NRICH.
How likely is that?
This issue's teacher package brings together all Plus articles on group theory, exploring its applications and recent breakthroughs, and giving explicit definitions and examples of groups. It also has some handy links to related problems on our sister site NRICH.
Have you got as many friends as you think?
The Eternity puzzle is back with a $2 million prize
This issue's teacher package brings together all Plus articles on vectors and matrices, exploring anything from the maths of computer movies to climate change. It also has some handy links to related problems on our sister site NRICH.
Some spurious statistics
This year's prize goes to Srinivasa S. R. Varadhan
If your team scores first in a football match, how likely is it to win? And when is it worth committing a professional foul? John Haigh shows us how to use probability to answer these and other questions, and explains the implications for the rules of the game.
Liz Newton finds that having a small brain doesn't stop you doing great things.
Loquacious maths
Food evolution




