More or Less: Behind the Stats

Recently a post did the rounds on Twitter, claiming that people who play tennis live on average 9.7 years longer than people who play other sports. The figure comes from a recent analysis of people's exercise habits in Denmark. But not everyone on Twitter was convinced. Tennis is a sport that in many countries is expensive to play and so attracts wealthier players. Couldn't it be the players' socio-economic status driving the trend? We speak to medical statistician Adam Jacobs, to understand what the study in question can, and cannot, say for certain. If you see any stats that look too good to be true and want us to check them out, email moreorless@bbc.co.uk. Presenter: Tim Harford Producer: Lizzy McNeill Series Producer: Tom Colls Editor: Richard Vadon Production Coordinator: Siobhan Reed, Maria Ogundele Sound Mix: James Beard Image Credit: Adrian Dennis, Getty Images Sport

Tim Harford investigates some of the numbers in the news. This week: (00:32) A government minister has informed the nation that average teacher pay in England is around £54,000. Radio 4 listeners are howling at the radio in disbelief. Surely someone from the IFS would be able to explain all this? We interview someone from the IFS to explain all this. (06:32) The Independent says that Russian soldiers survive an average of 20 minutes when they get to the frontline. How can they possibly know? We take a peek into the murky information ecosystem that surrounds the war in Ukraine. (15:00) A loyal listener has resent a burning question that - mortifyingly - he first asked us nearly three years ago: why is air travel cheaper than rail travel? We push our guilt deep, deep down then make it worse by challenging the premise of the question. (21:18) Is every shuffle of a deck of cards an unprecedented event in the history of the universe? It’s a bold claim, but maths YouTuber and comedian Matt Parker has done his homework. We invite him into the studio to make his case - and show off his shuffling skills. More or Less is the programme that looks at numbers and statistics in news and in life. We’re always looking for questions from listeners - you can contact us on moreorless@bbc.co.uk. Guests: Luke Sibieta - Research Economist at the Institute for Fiscal Studies Andrey Vladov - BBC Monitoring Mark Galeotti - author of Forged in War - A Military History of Russia from its Beginnings to Today Simon Calder - Travel Correspondent at the Daily Telegraph Matt Parker - Mathematician, comedian and YouTuber (Stand-up Maths) Presenter: Tim Harford Series Producer: Tom Colls Reporter: Josh McMinn Producers: Nathan Gower, Lizzy McNeill Editor: Richard Vadon Programme Coordinator: Maria Ogundele, Siobhan Reed Sound Engineer: James Beard

The Moon is one of the most captivating features of our night's sky, and apparently, one of the most suspicious.... For thousands of years, people have blamed the full moon for strange behavior. From ancient myths and the origins of the word lunacy to modern police folklore, the idea that a bright moon can influence human actions is one that many believe. But what does the data tell us? We spoke to Professor Eric Chudler, who has looked at crime rates and lunar cycles to discover whether the moon truly is the ultimate crime puppeteer. If you spot any suspicious numbers in the news or life and want us to investigate, please email in to: moreorless@bbc.co.uk. Presenter/Producer: Lizzy McNeill Series Producer: Tom Colls Editor: Richard Vadon Sound Mix: James Beard Production coordinator: Siobhan Reed

Tim Harford investigates some of the numbers in the news. This week: (00:23) Andy Burnham may not be Prime Minister yet, but he’s setting out his economic agenda, and its based on his old stomping ground, Greater Manchester. We ask whether the official figures that seem to show an economic miracle can be fully believed, and how much credit he deserves. (10:09) As our towns and cities get hotter, would turning to air conditioning really drive outside temperatures up by 10 to 12 degrees celcius? We learn about the fascinating world of ‘urban heat islands’. (15:40) We turn to homophones in an attempt to continue a running joke. This week, we follow six items about Wales with an item about whales - are our cetacean friends the carbon sinks of our dreams? Will we ever write a stranger paragraph? (22:10) Cult director and maths fanboy Werner Herzog has been waxing lyrical about the intruiging mysteries of prime numbers. Tim cracks out a surprisingly decent impression and we learn about one of the most inscrutable problems in mathematics - what’s not to like? More or Less is the programme that looks at numbers and statistics in news and in life. We’re always looking for questions from listeners - you can contact us on moreorless@bbc.co.uk. Guests: Paul Swinney - Chief Economist at The Data City Liam Sides - Associate Director at Oxford Economics Dimple Rana - Heat Resilience Leader at Arup Sue Grimmond - Professor of Meteorology, University of Reading Dr Olaf Meynecke - Marine Ecologist, Griffith University James Grime - Mathematician and star of YouTube channel Numberphile Special Guest Appearance: The Voice of Werner Herzog Presenter: Tim Harford Series Producer: Tom Colls Reporter: Nathan Gower Producers: Josh McMinn, Lizzy McNeill Editor: Richard Vadon Programme Coordinator: Brenda Brown Sound Engineer: James Beard

This year, the UK has had its hottest May and June days on record, with the mercury hitting the high thirties. But while the markings on a thermometer seem scientific and regular, the way we split up our calendar does not. Why, for instance, does May have 31 days and June have 30? To find out why our calendar has its modern form, we speak to Kristen Lippincott, former director of the Royal Observatory at Greenwich, and author of The Story of Time. If you have seen a number in the news you think we should take a look at, email moreorless@bbc.co.uk Presenter: Tim Harford Producer: Josh McMinn Series Producer: Tom Colls Programme Coordinator: Brenda Brown Sound Engineer: Giles Aspen Editor: Richard Vadon

Tim Harford investigates some of the numbers in the news. This week: (00:42) Former Chancellor of the Exchequer Sir Jeremy Hunt argues that you can earn far more on out of work benefits than you can on the minimum wage. We argue his figures are deceptive - and we’ve done the homework to prove it. (09:09) As the heatwave rises to a crescendo, people are saying that wet bulb temperatures could hit critical levels. Utterly mystified? So was our editor, so we made this item to explain all to him (and you). (14:34) In a tournament with so many teams, we’ve had to consult a university professor to understand the mysterious mathematical workings of the World Cup Draw. It’s even more complicated and confusing than VAR! (OK, it’s not that bad.) (19:00) Welsh comedian Elis James has a superpower - finding mutual connections with his fellow countrymen and women. So let’s add to the fun by providing a statistical framework upon which to understand his achievements. That’s how comedy works, right? More or Less is the programme that looks at numbers and statistics in the news and in life. We’re always looking for questions from listeners - you can contact us on moreorless@bbc.co.uk. Guests: Eduin Latimer - Senior Research Economist at the Institute for Fiscal Studies Dr Chloe Brimicombe - climate scientist and postdoctoral researcher at the University of Oxford Dr Kat Phillips - innovation research associate at the University of Warwick and a digital maths communicator under the name ‘KatDoesMaths’ Oliver Johnson - Professor of Information Theory, the University of Bristol Returning Special Guest appearance: Elis James: comedian and well-connected Welshman Presenter: Tim Harford Series Producer: Tom Colls Reporter: Nathan Gower Producers: Josh McMinn, Lizzy McNeill Editor: Richard Vadon Programme Coordinator: Brenda Brown Sound Engineer: James Beard

This surprising claim was spotted circulating on social media: ‘The United States has surpassed China and North Korea in deaths from malnutrition’. The claim used analysis from the Global Burden of Disease database for their sums. The data does indeed show that the US records more deaths from Malnutrition than China and North Korea. The rate in the US was 2.8 deaths per 100,000 compared to just 1.7 deaths per 100,000 for North Korea. From what we know about the two countries this seems unlikely, so what’s going on here? We talk to Dr Krstina Newport, Chief Medical officer for the American Academy of Hospice and Palliative Care Medicine to find out more. If you’ve seen a number in the news you think we should take a look at, email moreorless@bbc.co.uk Presenter: Tim Harford Producer: Lizzy McNeill Series Producer: Tom Colls Editor: Richard Vadon Production Coordinator: Brenda Brown Sound Mix: Duncan Hannant

Tim Harford investigates some of the numbers in the news. This week: (00:31) Claims have circulated on the internet that Europe sees a particularly high number of deaths from heat waves, especially when compared to the US. Can we really compare the statistics, and is air conditioning a silver bullet? (06:59) Sainsbury’s are making the switch from brown to white eggs, on the basis of claims about their carbon footprint - but how do you work this out? We talk to an egg man about eggs. A lot. (13:56) Are Conservative MPs frit? That’s what a Labour MP thinks after a recent PMQs saw no Conservative backbenchers ask a question. Are they really afraid to ask Keir Starmer a question? Or is it just probability? (19:20) In a series full of Welsh twists, another Welsh twist; have we been guilty of drastically underestimating the area of Wales by failing to account for its majestic mountains and plunging valleys? Topography is top of mind for our top team. More or Less is the programme that looks at numbers and statistics in news and in life. We’re always looking for questions from listeners - you can contact us on moreorless@bbc.co.uk. Guests: Gary Ford - policy advisor at the British Free Range Egg Producers Association Dr Laura Graham - computational and spatial ecologist at the University of Birmingham Dr  Jen Visser Rogers - statistician and chief scientific officer at Coronado Research. Special guest appearance: Elis James Presenter: Tim Harford Series Producer: Tom Colls Reporter: Lizzy McNeill Producers: Nathan Gower, Josh McMinn Editor: Richard Vadon Programme Coordinator: Brenda Brown Sound Engineer: Neil Churchill

The Great Crash of 1929 has faded into history, but financial journalist and author Andrew Ross Sorkin argues it holds vital lessons for today. Andrew came into the studio in London to discuss what we can understand about the crash in numbers, from ticker-tape running hours behind plunging stock prices to crucial metrics that sound the alarm bells before a financial crisis. Are they sounding today, in the middle of an AI stockmarket boom? Andrew’s new book is ’1929: Inside the Crash’. Presenter: Tim Harford Series Producer: Tom Colls Producer: Nathan Gower Editor: Richard Vadon Programme Coordinator: Brenda Brown Sound Engineer: James Beard

Tim Harford investigates some of the numbers in the news. This week: (00:32) The internet is abuzz with the claim that twenty-seven young migrants are hired for every British young person. We explore the truth behind this misleading claim. (08:40) Last year two nerds made a bet on our programme. Those nerds are Substacker Sam Freedman and Maxwell Marlow from the Adam Smith Institute, and they were betting on how the government’s introduction of VAT on school fees would affect pupil numbers. The results are in… (16:10) We revisit the topic of Welsh literacy after a raft of questions from loyal listeners. Could dual-language teaching explain Wales’ poor reading scores? (21:53) A Maths A-Level exam was so hard it inspired 30,000 people to sign a petition. But what made it so difficult, and will it make a difference to pupils’ grades? More or Less is the programme that looks at numbers and statistics in news and in life. We’re always looking for questions from listeners - you can contact us on moreorless@bbc.co.uk. Guests: Maxwell Marlow - Director of Public Affairs at the Adam Smith Institute Sam Freedman - Author of ‘Comment is Freed’ Substack John Jerrim - Professor of Education and Social Statistics at University College, London Sebastian Bicen - maths YouTuber and former school maths teacher Presenter: Tim Harford Series Producer: Tom Colls Reporter: Lizzy McNeill Producers: Nathan Gower, Josh McMinn Editor: Richard Vadon Programme Coordinator: Brenda Brown Sound Engineer: James Beard

In certain corners of the internet some suspicious numbers are cropping up again and again. People claiming that 400 churches have been burnt to the ground or attacked in an assortment of countries, including France, the US and Canada. So, what is going on? Is there a spate of anti-Christian crime sweeping the globe? We look into what the data actually tells us. If you've seen a number in the news you think we should take a look at, email moreorless@bbc.co.uk Presenter: Tim Harford Reporter/Producer: Lizzy McNeill Series Producer: Tom Colls Editor: Richard Vadon Production Coordinator: Brenda Brown Sound Mix: Dave O'Neill

Tim Harford investigates some of the numbers in the news. This week: The Daily Express claims that ‘Migrants will get half of all new homes’, based on a calculation from the Conservatives. We explain why that’s not what the numbers say, and ask what the Conservatives own record on migration and housing tells us. Does one in five Welsh pupils leave school functionally illiterate? We take a dive into the world of Welsh education and find the numbers tell a different story - but not an encouraging one. Accusations are flying about who’s responsible for the UK’s high borrowing costs. Does Liz Truss still cast a shadow over the bond market? Is Labour infighting to blame? Or are we missing the economic wood for the political trees? Duncan Weldon has the answers. And an answer to a question that literally only one person was asking: how many football pitches would fit inside Wales? More or Less is the programme that looks at numbers and statistics in news and in life. We’re always looking for questions from listeners - you can contact us on moreorless@bbc.co.uk. Guests: Ben Brindle - researcher at the Migration Observatory at the University of Oxford James Riding - Living Markets and Sustainability Editor at Inside Housing Kathy Rastle - Professor of Cognitive Psychology at the University of London Duncan Weldon - Economist and author of Blood and Treasure Rob Eastaway - mathematician and author of Maths on the Back of an Envelope Presenter: Tim Harford Series Producer: Tom Colls Reporter: Nathan Gower Producers: Josh McMinn, Lizzy McNeill Editor: Richard Vadon Programme Coordinator: Brenda Brown Sound Engineer: James Beard

On the 17th of May the World Health Organisation declared a new outbreak of Ebolavirus in the Democratic Republic of the Congo as an International Emergency. Ebola virus is an extremely nasty viral disease with a high death toll. But despite its severity, very little is known about the number of infections in this current outbreak, in part because this particular species of Ebola is a rare one. Headlines recently stated that modelling shows that the number of infections could be almost 1,000 more than recorded. We speak to Dr Ruth McCabe, an epidemiologist at Imperial College London, who worked on the modelling behind those estimates. Presenter: Tim Harford Producer: Lizzy McNeill Sound Mix: James Beard Production Coordinator: Brenda Brown Editor: Richard Vadon

Tim Harford investigates some of the numbers in the news. This week: Headlines have claimed that “healthy life expectancy” in the UK has fallen by two years. What does this actually mean? A new government report estimates that HS2 will cost almost double its original estimate. We ask where the money’s gone. Chancellor Rachel Reeves has reduced VAT on theme parks, aquariums and other summer fun. But will these savings get passed on to the consumer? And Tim gives a much-anticipated update on his recent marathon. Contributors: Stuart McDonald - actuary at LCP Health Analytics John Burn-Murdoch - Chief Data Reporter for the Financial Times Kate Lamble - journalist and presenter of ‘Derailed: The story of HS2’ Dan Neidle - founder of Tax Policy Associates Credits: Presenter: Tim Harford Reporter / Producer: Lizzy McNeill Producers: Tom Colls, Nathan Gower and John McMinn Production co-ordinator: Brenda Brown Sound mix: Neil Churchill Editor: Richard Vadon

What does it mean if you say that something is an epidemic? In the case of a virus, it usually means that it is spreading rapidly and that more and more people are getting infected. When a disease isn’t on the rise but is there in a population at a reasonably steady level, we tend to say that the disease is endemic. But what if the thing you’re talking about is not a virus, but a feeling? In 2023, the US surgeon general launched a report called “Our Epidemic of Loneliness and Isolation”, warning of the health harms of being lonely and socially isolated. The idea that there is an epidemic of loneliness didn’t start there - the term was already in use in the US in the 2010s. And it’s a phrase that’s still going strong, popping up in news stories on a regular basis. After that warning from the US Surgeon General, the World Health Organisation launched the Commission on Social Connection, with their director general warning that “more and more people are finding themselves isolated and lonely.” But is it true that loneliness rates are increasing? Is it right to say we’re in the midst of an epidemic of loneliness? It’s hard to find the data that backs up this claim. If you’ve seen a number in the news you think we should take a look at, email moreorless@bbc.co.uk CONTRIBUTOR: Professor Melody Ding, an epidemiologist and population behavioural scientist at the University of Sydney CREDITS: Presenter: Tim Harford Reporter: Tom Colls Production co-ordinator: Brenda Brown Sound mix: Dave O’Neill Editor: Richard Vadon

Tim Harford investigates some of the numbers in the news. On the programme: Last week, Annunziata Rees-Mogg took to X to post a claim about the proportion of sex offences in Dorset that are committed by asylum seekers, writing that “asylum seekers make up 0.8% of Dorset’s population and 44% of alleged sex offenses. So unbelievable I had to check.” We checked too, and the number isn’t right. In the last series of More or Less we suggested that nuclear power plant Hinkley C was spending so much on protecting the fish population that it would cost something like £250,000 per fish saved. We’ve had to take a look at that one too. Last year, we looked at a report by the Bible Society based on polling from YouGov. The Quiet Revival suggested that churchgoing was on the rise in the UK, with young men leading the trend. YouGov now have an update on that survey. How many caterpillars does a blue tit chick eat before it leaves the nest? In a recent nature documentary, Sir David Attenborough said the right number was 20,000. We’re not so sure. If you’ve seen a number in the news you think we should take a look at, email the more or Less team: moreorless@bbc.co.uk CONTRIBUTORS: Madeleine Sumption, Director of the Migration Observatory at Oxford University Professor David Voas, Emeritus Professor of Social Science in the UCL Social Research Institute Annette Jäckle, Professor of Survey Methodology at the University of Essex and a Deputy Director of the UK Household Longitudinal Study Dr Malcolm Burgess, Principal Conservation Scientist at the RSPB CREDITS Presenter: Tim Harford Reporter: Lizzy McNeill Producer: Nathan Gower and Josh McGinn Series producer: Tom Colls Production co-ordinator: Brenda Brown Sound mix: James Beard Editor: Richard Vadon

It’s said that AI could soon be coming for the jobs of artists, lawyers, and software engineers. But it might now also be threatening a role at the height of academia – are pure mathematicians safe? Last month, a Stanford mathematician woke up to an email, claiming to have the solution to a problem he'd been working on for seven years - a fifty-year-old conundrum known as "Erdos Problem 1196". The answer had been generated in just 80 minutes - by ChatGPT. Since the end of last year, AI has been providing solutions to a number of novel maths problems, but Problem 1196 is the first to raise eyebrows within the mathematical community. In this episode, we talk to the mathematicians who've worked on Problem 1196 and find out what the rise of AI could mean for the future of their field. CONTRIBUTORS: Katie Steckles, Mathematician and communicator Jared Duker Lichtman, Szegő Assistant Professor of Mathematics at Stanford University Liam Price, amateur mathematician Credits: Presenter: Charlotte McDonald Producer: Josh McMinn Series producer: Tom Colls Production co-ordinator: Brenda Brown Sound mix: Dave O'Neill Editor: Richard Vadon

According to the World Health organisation, smoking kills some 7 million people every year. It is one of the world’s leading causes of preventable death. Because smoking causes lung cancer and other awful health conditions, many smokers switch to vaping - using nicotine-based e-cigarettes. But the World Health organisation is also concerned about vaping. Last year they said 100 million people around the world are now using e-cigarettes, including millions of children, and warned that they were fuelling a new wave of nicotine addiction. But how do the health risks of these two means of getting nicotine into your bloodstream compare? According to a recent headline in the Daily Mail, they’re basically the same. Here’s the headline: “Vaping is linked to lung and mouth cancer in major study, as experts warn: 'It is NOT safer than smoking’” But is vaping really just as bad for you as smoking? CONTRIBUTOR: Professor Lion Shahab, Co-Director of the UCL Tobacco and Alcohol Research Group CREDITS: Presenter: Charlotte McDonald Reporter/producer: Tom Colls Production co-ordinator: Brenda Brown Sound mix: Dave O’Neil Editor: Richard Vadon

If you spend much time on social media, and we don’t necessarily recommend it, then you’ve probably come across a strange fascination with water consumption. Mainly, this is people telling you that using AI is terrible for the planet because of how much water it uses. We’ve already made a couple of programmes about the numbers in those arguments and, long story short, they probably aren’t saying what you think they’re saying. But on platforms like X, BlueSky, and TikTok, an opportunity to keep an argument going is rarely missed And one of the numbers that’s been enlisted in that glorious cause concerns the water that’s used for a seemingly unrelated past-time - eating beef. Here’s an example from a user on X: “A kilogram of beef requires over 15,000 litres of water to produce,” they wrote. “A vegan who uses ChatGPT every day is living a more sustainable lifestyle than someone who regularly eats beef while boycotting AI.” Ignoring the AI part, is that true? Does it actually take 15,000 litres of water to produce a kilogram of beef? It turns out that the number isn’t wrong, but it probably isn’t saying what you think it’s saying. If you’ve seen a number you think we should take a look at, email the More or Less team: moreorless@bbc.co.uk CONTRIBUTORS: Mesfin Mekonnen, Assistant Professor at the University of Alabama Mark Mulligan, Professor of Physical and Environmental Geography at King's College London Tim Hess, Professor of Water and Food Systems at Cranfield University CREDITS: Presenter: Charlotte McDonald Producer: Mhairi MacKenzie Series producer: Tom Colls Production co-ordinator: Brenda Brown Sound mix: Emma Harth Editor: Richard Vadon

Vaccine policy in the US is something of an ideological battleground. Health Secretary Robert F Kennedy Jr is a vaccine sceptic, and since taking office he has attempted to remake US vaccine policy. In March a judge blocked his proposal to cut the number of jabs that are recommended for kids. At the same time, last year saw the worst measles outbreak in the US in decades. There were more than 2000 cases last year, and three people died. There have been more than 1500 cases so far in 2026. There’s a lot going on, so it’s possible the public’s views on vaccination are shifting. A new poll published by online news site Politico added a big claim into the mix. According to the headline “more Americans doubt vaccine safety than trust it”. But is that what the survey actually found? Dr David Higgins, a paediatrician and public health assistant professor who writes a Substack called Community Immunity, explains why he believes the headline is misleading. If you've seen a number in the news you think we should take a look at, email moreorless@bbc.co.uk Presenter: Charlotte McDonald Series producer: Tom Colls Production co-ordinator: Brenda Brown Sound mix: Neil Churchill Editor: Richard Vadon