David Spiegelhalter (UK, out now); (US, 4 March 2025))
I am not a twin, but I share a birthday with my sister, who is three years older than me. When I tell people, I normally get one of two reactions: either a lewd joke about how nine months earlier must have been a special date for our parents, or a 鈥渨hat are the chances?鈥�
In my ignorance, I have always assumed it was simply 1 in 365. And in his new book The Art of Uncertainty: How to navigate chance, ignorance, risk and luck, statistician David Spiegelhalter explains why I am correct: 1 in 365 is the chance of any individual being born on a particular day of the year, but the chance that a pair of non-twin siblings would share a birthday is still 1 in 365.
Advertisement
The Art of Uncertainty follows on from Spiegelhalter鈥檚 bestseller The Art of Statistics. An emeritus professor of statistics at the University of Cambridge, he was on hand during the covid-19 crisis to help us think through what the statistics can and can鈥檛 tell us. Spiegelhalter has spent his career crunching numbers to learn from past events and assess what may happen in the future. With this thought-provoking new book, he aims to give readers a window into how they can apply this in their own lives.
A book on statistics will inevitably be number-heavy and full of terms not generally seen outside a classroom, such as 鈥淏ayes鈥檚 theorem鈥� and 鈥淧oisson distribution鈥�. Spiegelhalter warns readers early on that his book will be complex at times, but the nature of the subject makes this unavoidable. He does as well as he probably can at explaining statistical words and phrases in familiar terms, providing a glossary at the back of the book and a summary box at the end of each chapter for a snapshot of the points he has covered.
By digging into the data, Spiegelhalter manages to set straight some of life鈥檚 everyday uncertainties. For instance, could eating burnt toast really give you cancer? Well, if you were to eat an enormous 160 slices a day, you would still only be putting yourself at low risk. While this sort of information is interesting, I was most keen to learn how I could use statistics to bring about more fortuitous events in my life, preferably lottery wins.
I was thrilled to learn that my health won't suffer too much if I mistakenly burn my toast in the morning
It turns out that luck is a funny thing, as Spiegelhalter demonstrates by calling on a historical and personal example. He writes about how his grandfather Cecil described being 鈥渂lown up鈥� during the first world war, surely not a lucky event by anyone鈥檚 definition. But it meant that afterwards, Cecil was considered unfit for front-line duties and spent the rest of the conflict away from the fighting. This, of course, may well have protected him from sustaining a more serious, or even fatal, injury.
This is a point Spiegelhalter returns to again and again. Both the degree of luck that we feel we experience and the level of risk we are willing to tolerate vary from person to person and depend on the context.
Calling on the wisdom of psychologist Richard Wiseman, Spiegelhalter believes that good luck ultimately boils down to four traits: the ability to take advantage of opportunities, having good intuition about how to act, positive expectations that spur confidence and the resilience to turn setbacks to your advantage. This is a lot less glamorous than crystals and sorcery, but it is scientifically sound.
I didn鈥檛 finish The Art of Uncertainty with the knowledge of how to manipulate luck to effortlessly make my fortune. But I was still thrilled to learn that my health won鈥檛 suffer too much if I mistakenly burn my toast in the morning.
I also now have a statistically accurate response rather than a semi-informed guess when people ask what the chance is of me and my non-twin sister sharing our birthday. Whether that will put an end to all those parent-sex jokes remains to be seen.
Getting to grips with uncertainty
See David Spiegelhalter speak at 快猫短视频 Live on 12 October
快猫短视频 book club
Love reading? Come and join our friendly group of fellow book lovers. Every six weeks, we delve into an exciting new title, with members given free access to extracts from our books, articles from our authors and video interviews.
