More or Less: Behind the Stats - Does a single AI query use a bottle of water?

We’re living through boom-times for Artificial Intelligence, with more and more of us using AI assistants like ChatGPT, DeepSeek, Grok and Copilot to do basic research and writing tasks.

But what is the environmental impact of these technologies?

Many listeners have got in touch with More or Less to ask us to investigate various claims about the energy and water use of AI.

One claim in particular has caught your attention - the idea that the equivalent of a small bottle of drinking water is consumed by computer processors every time you ask an AI a question, or get it to write a simple email.

So, where does that claim come from, and is it true?

Reporter: Paul Connolly Producer: Tom Colls Production co-ordinator: Brenda Brown Sound mix: Donald McDonald Editor: Richard Vadon

More or Less: Behind the Stats - Are one in six children living through war?

In the midst of the television coverage of Soccer Aid, a celebrity soccer match organised by Unicef, the audience was told that “one in six children around the world are currently living through war”.

Listener Isla got in touch with More or Less to ask whether the claim was correct, so we tracked down the source to an organisation called the Peace Research Institute Oslo.

Research director Siri Aas Rustad tells us how they worked out a figure for the number of children living near to a “conflict” and the big differences between that and something most people would think of as “war”.

If you’ve seen a number you think we should look at, email the team on moreorless@bbc.co.uk

Presenter: Lizzy McNeill Producer: Nicholas Barrett Series producer: Tom Colls Production co-ordinator: Brenda Brown Sound mix: Giles Aspen Editor: Richard Vadon

More or Less: Behind the Stats - Why Manchester United can afford to play badly

Manchester United are terrible, even according to their own manager. Last season saw their worst ever performance in Premier League history.

But at the same time, according to Forbes magazine, they’re still the second most valuable football club in the world.

How is that possible?

Tim talks to Kieran Maguire, a football finance expert and the author of The Price of Football, to find out the secret of Manchester United’s financial success.

Presenter: Tim Harford Producer: Nicholas Barrett Series producer: Tom Colls Production co-ordinator: Brenda Brown Sound mix: Neil Churchill Editor: Richard Vadon

More or Less: Behind the Stats - Can drinking one less bottle of coke a day halve obesity?

Tim Harford investigates some of the numbers in the news and in life. This week:

Is the secret to halving obesity rates really just a matter of cutting back on one fizzy drink a day?

How many new babies in the City of London have a foreign-born parent? And since fewer than one baby a week is actually born in the City of London, how much should we care?

Electricity in the UK is more expensive than almost anywhere else. Why? And is it anything to do with wind turbines?

And we help out rival Radio 4 programme Start the Week with a claim about churches.

If you’ve seen a number in the news you think we should take a look at, email the team: moreorless@bbc.co.uk

More or Less is produced in partnership with the Open University.

Presenter: Tim Harford Reporter: Lizzy McNeill Producer: Nicholas Barrett and Nathan Gower Series producer: Tom Colls Production co-ordinator: Brenda Brown Sound Mix: James Beard Editor: Richard Vadon

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More or Less: Behind the Stats - The economics of war: Vikings, Conquistadors and Vietnam

How does economics help us understand conflicts through history?

That’s the question that economist and journalist Duncan Weldon tries to answer in his new book, Blood and Treasure.

Tim talks to Duncan about the economic perspective on Viking raiders, Spanish conquest and the Vietnam war.

Presenter: Tim Harford Producer: Tom Colls Production co-ordinator: Brenda Brown Sound mix: Neil Churchill Editor: Richard Vadon

More or Less: Behind the Stats - Is the UK seeing a Christian revival?

Tim Harford looks at some of the numbers in the news and in life. This week:

Is church-going making a comeback in the UK?

Is it true that every day, 1000 people begin claiming personal independence payments, or PIP?

When the government talks about how it “returns” illegal immigrants, what does it mean?

Can a new telescope really see golf balls on the moon?

If you’ve seen a number you think looks suspicious, email the More or Less team: moreorless@bbc.co.uk

More or Less is produced in partnership with the Open University.

Presenter: Tim Harford Producers: Lizzy McNeill, Nicholas Barrett, David Verry Series producer: Tom Colls Production co-ordinator: Brenda Brown Sound mix: Gareth Jones Editor: Richard Vadon

More or Less: Behind the Stats - Has Russia suffered a million casualties in the Ukraine war?

It’s been over three years since Russia’s full-scale invasion of Ukraine and the human toll is growing on both sides.

Recently, politicians and journalists have declared a grim milestone, one million Russian casualties.

But is this number accurate?

Tim talks to Seth Jones, from the Center for Strategic and International Studies, and Olga Ivshina, from the BBC Russian service, to investigate this statistic.

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

Presenter: Tim Harford Producer: Nicholas Barrett Series producer: Tom Colls Production co-ordinator: Brenda Brown Sound mix: Gareth Jones Editor: Richard Vadon

More or Less: Behind the Stats - Why is data on grooming gangs so bad?

Tim Harford looks at some of the numbers in the news and in life. In this episode:

Why is the data on the ethnicity of grooming gangs of such poor quality?

Iran has apparently enriched uranium to 60%, but what does that number mean?

Adam Curtis’s latest series, Shifty, includes claims about Margaret Thatcher’s rise to power. We ask Sir John Curtice, polling king of election night, if they’re accurate.

And we ask an economist to explain why being pillaged by a Viking might be more lucrative than you’d imagine.

If you’ve seen a number in the news you think needs a stern look, email the team: moreorless@bbc.co.uk

More or Less is produced in partnership with the Open University.

Presenter: Tim Harford Reporter: Josephine Casserly Producers: Nicholas Barrett, Lizzy McNeill and David Verry Series producer: Tom Colls Production coordinator: Brenda Brown Sound Mix: Gareth Jones Editor: Richard Vadon

Start the Week - Sanctuary, refuge and exile

Sanctuary is an ancient idea of a place of refuge or freedom from harm. It has deep roots in the history, literature and myths of many cultures. Marina Warner’s new book Sanctuary explores travelling tales and concepts of hospitality and home - suggesting that myths, stories and works of art can be places of sanctuary too.

The story of leprosy is a story of isolation and exclusion over thousands of years. In his book, Outcast, Oliver Basciano has written about his journey across the hinterlands of the world to demystify the lives of those who have been ostracised. He argues that the image we still hold onto of medieval leprosy is a nineteenth-century myth invented to justify the gross mistreatment of patients in the name of colonial, religious and economic exploitation.

Churches are a spiritual home for some 200 million Christians worldwide, but they often hold a fascination and interest for the most committed atheist. A church is a place of sanctuary, but also a place where the drama of life is played out. Fergus Butler-Gallie is an Anglican priest and his new book Twelve Churches explores the history of Christianity through the places worshippers have built.

Presenter: Tom Sutcliffe Producer: Ruth Watts

More or Less: Behind the Stats - How to spot a suspicious statistic

Untruths sneak into our lives in all kinds of ways. Sometimes they’re outright lies. Blatant misinformation.

But in this episode, we’re going to talk about something else - those sneaky numbers and claims that bounce around our society and that aren’t exactly false, but are leading you down the wrong path.

That’s the subject of a book called May Contain Lies by Alex Edmans, a professor of finance at London Business School.

Tim talks to Alex about the statistical claims that might not be wrong, but aren’t right either – and how to make sure you aren’t fooled by them yourself.

Presenter: Tim Harford Producer: Tom Colls Production co-ordinator: Brenda Brown Sound mix: Andrew Garratt Editor: Richard Vadon