Tails you win. The science of chance.

Through interviews, augmented-reality graphics and fascinating history Professor David Spiegelhalter tries to pin down what chance is and how it works in the real world. Spiegelhalter contextualises the idea of chance by applying the principle of flipping a coin to unpredictable and chaotic events. Attitude to the risk of environmental disaster is examined through footage surrounding the 1989 San Francisco and an interview with seismologist Professor Mary Lou Zoback. Spiegalhalter suggests probability is as much a matter of judgement as it is of arithmetic and, while chance is inescapable, if it can be understood it can be used to advantage. Spiegalhalter looks at the 16th century published 'Book on Games of Chance' by Gerolamo Cardano. In Las Vegas professional gambler Mike Shackleford discusses how he uses probability to improve his chance at casinos. Games designer Chris Brune talks about the human interaction with gambling machines. Shackleford examines how card counting can be used to influence gambling. Spiegelhalter looks at man’s relationship with death, arguing for most of human history death was considered unpredictable. Around 300 years ago scientists began to investigate the mathematical chances of death for each individual and it was found that studying one group of people could allow one to estimate chances of death at each age, thus turning death from a divine punishment into a predictable force of nature. Speigelhalter explores how Edmund Halley first successfully applied the maths of chance to human lives. Actuary Margaret de Valois examines Halley’s use of data to identify trends, which led to a revolutionary discovery that the older one is there is more chance of death. Spiegelhalter discusses the role chance and risk plays in life expectancy. Health statistics are reviewed to help better understand the risk and benefits of lifestyle choices. When talking about risk Spiegelhalter uses the micromort unit which represents a one in a million chance of death. With a higher risk of dying at an older age Spiegelhalter suggests extra micromorts from risky activities have less significance the older you are. The nature of risk is explored through ‘Premium Bonds’; a scheme developed by mathematicians which used chance to help investors win prizes. Dame Stephanie Shirley discusses how the creation of a special built computer; Electronic Random Number Indicating Equipment ‘E.R.N.I.E’ allowed for complete randomness. Spiegelhalter uses the book ‘One Million Random Digits’ to explore the patterns rules and structure of randomness. By examining the lottery he argues random is predictable and has its own shape. Spiegelhalter discusses coincidences and our reaction to them. Cricketer Ed Smith talks about his ideas of luck in the sports world. Looking at scientific revolutions, Spiegelhalter discuses why chance exists in nature. The theory of scientific determinism suggests with the right mathematics and intimate knowledge of everything then uncertainty will disappear and the future can be predicted. In practice prediction has proved frustratingly hard due to the nature of chaos in which tiny influences can have unpredictable consequences. To demonstrate our limitations of understanding probability Spiegelhalter looks at Heisenberg’s uncertainty principle, leading him to question what chance actually is. Scientists have used chance to convert blind uncertainty into computable probability and during the Cold War the 'Monte Carlo Method' was developed to deliver more accurate probability. Today the Monte Carlo Method is used in an array of fields including the weather. Professor Tim Palmer explores methods of weather forecasting that allow for informed decisions by stressing probability rather than prediction. Spencer Dale discusses the idea of ‘unknown unknowns’ and the role they play in the economy.