## probability

New episodes of *Pointless*, the addictive TV quiz show, return today! Celebrate with John Haigh and some fascinating *Pointless* maths!

Take a quick trip to the foundations of probability theory.

Randomness is surprisingly hard to define. Fortunately the mathematical language we use to describe it is beautifully well defined.

The second guiding principle in probability theory is more subtle – universality.

Symmetry is one of the two guiding principles in understanding probabilities – if different outcomes are equivalent they should have the same probability.

Here's a resolution for one of probability theory's most famous paradoxes.

Is the proposed ABBA rule for penalty shootouts really fairer than the existing rule? Maths shows that it is, and also suggests another, more subtle rule.

What's wrong with this probability argument?

The probability distribution that measures success and failure.

The practice of overbooking has made uncomfortable headlines lately. But how do airlines decide how many tickets to sell for a flight? Here's the maths.