David Spiegelhalter, one of our favourite experts on statistics, recently joined David Attenborough, Bill Bryson and other eminent contributors on the Royal Society's People of Science series. You can watch the video here.

Forecasting election results is a sophisticated business.

This may seem like an odd question — after all, he’s won — but it opens up some deep philosophical issues surrounding probability. David Spiegelhalter investigates how probability can be defined.