More or Less: Opinion polling, Kevin Pietersen, and stacking Lego

Summary

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Podcast Summary: More or Less – Opinion Polling, Kevin Pietersen, and Stacking Lego

Date: November 30, 2012
Host: Tim Harford (BBC Radio 4)
Featured Guests: Laura Gray, Peter Kellner (YouGov), Rob Eastaway (Cricket Statistician), Susan Spash (Accountant), Andrew Lester (Institute for Fiscal Studies), Dr. Ian Johnston (Open University), Ruth Alexander, Duncan Titmarsh & Ed Diamond (Bright Bricks)

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Episode Overview

In this episode of More or Less, Tim Harford guides listeners through the misuse (and occasional enlightenment) of statistics in public debate and everyday questions. The team tackles the reliability of opinion polls on press regulation, scrutinizes cricketing stats in the light of Kevin Pietersen’s reputation, debunks misconceptions about millionaire flight over UK tax rates, questions the economics of minimum alcohol pricing, and investigates a burning question from Reddit—how high can you stack Lego before the bottom brick crumbles?

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1. The Reliability of Opinion Polls on Press Regulation (00:46–07:17)

Key Points & Insights

• Context: Following Lord Leveson's report on press regulation, YouGov polls showed dramatically different public opinions—depending solely on how the questions were phrased.
• Example Discrepancy:
  • 79% in favor of an independent body for press complaints when not mentioning MPs, per Media Standards Trust poll.
  • Only 24% in favor when explicitly mentioning a body “set up through law by Parliament, with rules agreed by MPs” (The Sun’s poll).
• Analysis:
  • The wording and framing of poll questions radically affect results.
  • Polls published by interested parties (e.g., campaign organizations, newspapers) often reflect their chosen framing.

Notable Quote

“We’ve discovered that the wording of the question is crucially important.”
— Tim Harford [02:55]

• YouGov’s Peter Kellner explains that contrasting results reflect not public indecision but people’s unfamiliarity with the technicalities of the debate:

“The fact that our answers appear to depend so much on the precise wording suggests that people have not been following the precise debate about statutory versus non-statutory regulation very closely.”
— Peter Kellner [04:19]

• Transparency in Polling:
  • YouGov publishes full poll results online for public scrutiny, decreasing the chance of selective misrepresentation.

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2. Cricket Statistics and the Kevin Pietersen Question (07:17–13:16)

Key Points & Insights

• The Listener’s Question: If your life depended on a batsman scoring a century, would you choose Kevin Pietersen?
• Flaws in Batting Averages:
  • Batting averages mask inconsistency and context (strong opposition, match importance, pitch conditions, team situation).
  • Not-outs can inflate batting averages artificially.

Statistical Nuances:

• Consistency vs. Brilliance:
  • A batsman’s consistency isn’t always desirable; in 'do-or-die' situations, erratic players may be better bets for centuries.
• Proportion of Team’s Runs:
  • Pietersen scores about 15% of his team's runs when he plays, compared to Ian Bell’s 12.5%.
  • Pietersen is “middling” in inconsistency.

Notable Exchange

“One other flaw is that you can actually distort your average by having plenty of innings that are not out.”
— Rob Eastaway [08:28]

• Historical Perspective:
  • Best batsmen for the once-in-a-lifetime century:
    • Current England player: Alastair Cook
    • Active world player: Michael Clarke
    • All-time: Donald Bradman (scored a century every fourth innings)

“He was incredible.”
— Rob Eastaway on Bradman [13:07]

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3. Debunking: Did Two Thirds of Millionaires Leave the UK to Avoid the 50p Tax Rate? (13:16–15:20)

Key Points & Insights

• Misleading Headlines:
  • Telegraph's “2/3 of millionaires left Britain” headline is challenged:
    • The headline refers to people earning over £1 million annually, not people holding £1 million in assets.
    • In the relevant tax year, 16,000 people earned over £1m; after tax changes, that number fell sharply.
• Reality:
  • The drop in “million-pound earners” was mostly due to tax planning—income was recognized before higher taxes kicked in, not mass emigration.

“They were tax planning. Yes. That would be my take on it.”
— Susan Spash [15:15]

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4. Impact of Minimum Alcohol Pricing (15:20–18:08)

Key Points & Insights

• Policy:
  • The UK Home Office proposed a minimum price of 45p per unit of alcohol.
• Analysis:
  • Contrary to the idea that the policy would only affect the cheapest drinks, nearly 60% of off-licence alcohol would be impacted, including 85% of cider and Perry, and 72% of lager.
• Distributional Impact:
  • Poorer households would see a bigger relative increase in household spending.
• Effectiveness:
  • Evidence shows higher alcohol prices reduce overall consumption. It's "fairly safe" drinking would decline, but less certainty whether heavy/problem drinkers would be deterred.

“I think it’s a fairly safe bet that drinking will go down as a result of a minimum price.”
— Andrew Lester [17:39]

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5. How High Can You Stack Lego Before It Breaks? (18:08–23:07)

Key Points & Insights

• The Experiment:
  • Open University engineers (Dr. Ian Johnston and team) tested the crush force of a 2x2 Lego brick.
• Method:
  • Used a servo hydraulic testing machine ("we're setting it up to do it automatically so that we can all back out of the room, so that none of us is in range when the thing goes bang." — Dr. Ian Johnston [00:36 & 20:13])
• Result:
  • Average maximum load before failure: 4,240 Newtons, roughly 432 kg.
  • This translates into stacking 375,000 Lego bricks, or a tower 3,591 meters high (~11,781 feet), before the bottom brick melts under the weight.

“375,000 bricks, over three and a half kilometers high, and that’s what it would take to make that bottom brick crack, or rather, ooze.”
— Tim Harford [21:57]

• Practicality:
  • Human Lego builders say it's "structurally impossible" to actually build such a tower—bending, swaying, and buckling would sabotage any real attempt above a few meters.

“As soon as you get beyond three or four metres tall, there’s almost no way that you can take out all of the kinks… It would be totally structurally impossible to do it.”
— Rob Eastaway [22:55]

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Memorable Moments & Quotes

• On poll framing:

  “The whole issue of framing the debate is part of what the debate is about.”
  — Peter Kellner [06:24]

• On misleading statistics:

  “The headline is slightly misleading, to say the least.”
  — Susan Spash [14:11]

• On Lego testing:

  “The brick just kind of melted.”
  — Ruth Alexander [21:01]

• On parental pride:

  “If this makes it to broadcast, she’s going to think my entire career has been worthwhile. Thanks, Mum.”
  — Dr. Ian Johnston [23:54]

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Timestamps for Key Segments

• [00:46–07:17] – Press regulation poll discrepancies, YouGov's Peter Kellner explains framing
• [07:17–13:16] – Kevin Pietersen, cricket statistics, and betting your (statistical) life
• [13:16–15:20] – Millionaires, 50p tax rate, and misleading headlines (with Susan Spash)
• [15:20–18:08] – Alcohol minimum pricing: who pays and does it work? (with Andrew Lester)
• [18:08–23:07] – The Lego brick experiment: science, safety goggles, and practical limits

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Conclusion

This episode of More or Less is a tour de force in statistical skepticism and practical science: exposing the subtleties in opinion polls, the quirks of cricketing metrics, the reality behind tax headlines, the economics of alcohol pricing, and the ultimate limits of Lego stacking. True to the show’s spirit, every segment is laced with humor, clarity, and a mission to help listeners think a little more critically about numbers in the news and everyday life.

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Transcript

[Tim Harford]

Thank you for downloading this edition of More or Less from BBC Radio 4. Here's Tim Harford.

Hello and welcome to More or Less the sandbag holding back the flood of bad statistics in the news and in life. This week, we'll be asking whether if your life depended on someone scoring a century in cricket, you'd send Kevin Peterson out to bat. We'll look at the claim that two thirds of millionaires left the UK to avoid the 50p tax rate. And Ruth Alexander answers the important question of how high you can build a Lego tower before the bottom brick collapses.

[Dr. Ian Johnston]

Because we're beginning to get a little bit nervous about the number of bits that might fly into when it's failing, we're setting up to do it automatically so that we could all back out of the room, so that none of us is in range when the thing goes bang.

[Tim Harford]

But first, this week, Lord Leveson published his report into the culture, practice and ethics of the press and made recommendations about how it should be regulated in the future. From the benches of the House of Commons to homes across Britain, people have been talking about what the future of the press should be. Should there be statutory regulation, regulation or self regulation? The online polling company YouGov did their own research into what the public thought about this much debated topic. Laura Gray's been looking at these polls. Laura, hello. What did they conclude?

[Laura Gray]

Ok, so first let's look at a poll carried out by YouGov and published by the Media Standards Trust, which is an organisation that's been critical of self regulation in the past. Now, this shows that 79% of people think there should be an independent body established by law, which deals with complaints and decides what sanctions there should be if journalists break agreed codes of conduct.

[Tim Harford]

79%. Completely comprehensive.

[Laura Gray]

But if you look at another poll, again done by YouGov, only this time published by the sun, and the sun, of course, will be on the receiving end of any regulation. You'd see that only 24% of people want a regulatory body set up through law by Parliament, with rules agreed by MPs.

[Tim Harford]

So essentially, we've got two polls carried out by the same polling company on the same question, and they draw totally different conclusions.

[Laura Gray]

It's not quite the same question. There are crucial differences. The question for the Media Standards Trust asks people if they want an independent body established by law. It also doesn't mention MPs when the question is asked this way. 79% think statutory regulation is a good idea. But the question for the sun asks people if they want a regulatory body set up through law by Parliament, which, with rules agreed by MPs, with no mention of the word independent, and asked this way, only 24% of people want it. But actually, if you look at the results in both polls, the results aren't so dissimilar. People want a new law to force the media to behave better, but they don't want MPs making that law, even

[Tim Harford]

though that is, of course, the way that parliamentary democracy actually works. Well, thank you, Laura. We've discovered that the wording of the question is crucially important. And that reminds me of a very famous sketch in the 1980s sitcom, yes, Prime Minister.

[Sir Humphrey Appleby]

Well, Bernard, you know what happens. Nice young lady comes up to you. Obviously you want to create a good impression. You don't want to look a fool, do you?

[Rob Eastaway]

No.

[Ruth Alexander]

No.

[Sir Humphrey Appleby]

So she starts asking you some questions. Mr. Willie, are you worried about the number of young people without jobs?

[Rob Eastaway]

Yes.

[Sir Humphrey Appleby]

Are you worried about the rise in crime among teenagers?

[Rob Eastaway]

Yes.

[Sir Humphrey Appleby]

Do you think there's a lack of discipline in our comprehensive schools? Yes. Do you think young people welcome some authority and leadership in their lives?

[Tim Harford]

Yes.

[Sir Humphrey Appleby]

Do you think they respond to a challenge? Yes. Would you be in favor of reintroducing National Service?

[Rob Eastaway]

Oh, well, I suppose I might.

[Sir Humphrey Appleby]

Yes or no? Yes, of course you would, Bernard. After all you've told, you can't say no to that. So they don't mention the first five questions and they publish the last one.

[Tim Harford]

The incomparable Sir Humphrey Appleby, explaining the facts of statistical life to Bernard Woolley. So, to return to the question of statutory regulation of the press, I summoned Peter Kellner, the president of YouGov, to explain whether he was a tool in the hands of the spin doctors or doing God's work.

[Peter Kellner]

The fact that our answers appear to depend so much on the precise wording suggests that people have not been following the precise debate about statutory versus non statutory regulation very closely. When you ask about things that people feel strongly about, I don't know, about Europe or about capital punishment or whether they like or dislike David Cameron, it doesn't really matter very much what the wording is, but where you've got things that people have not yet fully engaged with, the wording does matter.

[Tim Harford]

Now, Peter, understandably, you're approaching this from the point of view of how do we find out what people want? But of course, opinion polls are used to find out what people want. But opinion polls are also used by people to make their case, to say, people support us, people want what we want. Now, YouGov has been commissioned by three different bodies with three different axes to grind and has come up with three different conclusions. Are you worried that you might be being manipulated or being used by newspapers, by campaigning bodies who want to make a particular case?

[Peter Kellner]

No, I don't think we are. I mean, the first thing is we in the end have a veto over the questions. The questionnaire is a matter of negotiation between us and the client and we frequently refuse to ask questions that particular clients want us to ask. And occasionally we've turned down the commission altogether and then seen other pollsters ask questions which we've refused to ask. The problem is that often there is not a simple, obviously neutral, all embracing way of asking the question. Because the actual debate that's going on is a debate about framing. And if we take Leveson, what you've been seeing is the press, especially the tabloid press, saying this is about state control of the media, state licensing, something that Britain abolished 300 years ago. That is how they're framing it. And it is not unreasonable to find out what people think if you frame a question in those terms. Other people are saying what we need is absolutely independent, fearless regulation that the newspapers have to abide by and can't get round. So they're framing it that way. So I think it is perfectly reasonable to ask the questions in different ways, because the whole issue of framing the debate is part of what the debate is about. But that's why, actually I'm delighted that we've asked questions for both sides of the argument because we put it all up on our site. People can see exactly what we've asked. They can see the bits that the sun picked and which they didn't pick. And actually, it's not simply a question of whether people notice it in the sun or not, because people do look at what we put on their site and people then start blogging and tweeting about it. This is a very, very transparent process.

[Tim Harford]

Peter Kellner of YouGov, you're listening to more or less on BBC Radio 4 with me, Tim Harford. We're not ones to be churlish here on More or Less, but we're about to ask some hard questions about Kevin Peterson and the quality of his batting. I'm sure he can take it. He may be the darling of English cricket, but if your life depended on someone scoring a century, would you send KP out to bat? Peter Harvey sent us a letter all the way from Perth in Australia to ask us that very question. And he also KP is often likened

to Marmite love Or hate, but nothing in between. If there is consistency, however, it's in the view that the English batting lineup is weaker without him in support. His average score when in an England shirt is offered as evidence and he's often spoken of as a match winner. We can't do without. But is he or can we?

So does Kevin Peterson's batting average tell us much about how well he might perform in this imaginary life saving challenge? Rob Eastaway is a member of the association association of Cricket Statisticians and he co devised the International Cricket Council's World rankings which have been developed to address some of the flaws in the batting average.

[Rob Eastaway]

Averages are not a bad reflection of what you've done over a whole career, but they do have a number of flaws, especially looking at a shorter period of time. First of all, they give no sense of how inconsistent a batsman is. You get 0, 100, naught 100, that's the same average as if you get 50 every time. They also take no account of who you've made those runs against or whether it was a low scoring match. And they were more significant runs. And they don't really reflect form either. So they will tend to deaden over your career. Your average moves less and less the more matches that you've played. One other flaw is that you can actually distort your average by having plenty of innings that are not out. So it would be possible for a really hopeless batsman coming in at the end to score one run and be out and then for his next 99 innings get one not out, one not out and he'd end up with an average of 100, which might imply he's a great batsman. In fact, he just strung together a whole series of knot out innings.

[Tim Harford]

Rob, you've been thinking about Peter's question, I suppose two questions actually, specifically on the question of betting your life on Kevin Peterson scoring a century. Presumably you don't want a consistent batsman because a typical high quality batsman would average 45 or 50, wouldn't average anywhere near 100, which is a century. So you actually want someone who's wildly inconsistent rather than someone who always gets 40, 45, 50, 60 and then gets out. You want somebody who will occasionally score 100, otherwise you've got no chance.

[Rob Eastaway]

Well, that's a really interesting point and cricketers would argue that either way. So a consistent bat. It's nice to have someone you know you can rely on a good solid base for the team to build their innings around. Someone who scores 50 every time and someone like Andrew Strauss who's now retired was a good consistent batsman. But then, yes, they're unlikely to be the ones who do the spectacular match winning performance as Kevin Peterson did last week with his 186.

[Tim Harford]

Okay, so you're ducking this question of betting your life on a century. That's probably very sensible. We don't encourage such bets. So to come back to the question of whether he's valuable to the England team, you said the context matters.

[Rob Eastaway]

Well, yes. If you're playing against a really strong side like Australia, then it's going to be harder to score runs than if you're playing against one of the weaker sides like Bangladesh. So what you'd really want to do is adjust the runs for the context of the game to say who's it against and what proportion of the team's runs are you actually scoring?

[Tim Harford]

So how does Peterson rate? Does he make big scores when other players are not scoring? It's often said about Ian Bell, I think that he only scores centuries when someone else has already scored a century. I mean, is that true about Bell and is Peterson different?

[Rob Eastaway]

Yeah, there is some truth in that. If you look at just proportion of teams runs scored, for example, Kevin Peterson's close to 15% when he plays, he scores about that, whereas ian Bell is 12 and a half percent. So there's quite a gap there.

[Tim Harford]

And would you say that Kevin Peterson is an inconsistent batsman? He recently scored 186. The previous Test he scored 19. I'm no cricket expert, but that doesn't seem consistent.

[Rob Eastaway]

He's about average, as it were. One way you'd look at this would be looking at a player's scores and looking at what's called the standard deviation of those scores, how much they tend to fluctuate from the average. And Peterson is actually fairly middling in terms of that.

[Tim Harford]

Let's just step back from this for a second. You've given us all kinds of different ways of measuring the performance of Kevin Peterson. The fact that there are so many different ways to measure it, does that mean the statistics aren't really telling us anything at all? Or are you a believer that actually collecting this kind of data could actually help? For instance, the England team managers pick the best players.

[Rob Eastaway]

In the long run, the cricket statistics just don't lie that a batsman's average over his whole career gives a pretty good indication of how good he is. I think cricket is a harder sport for the analysts to work off data from and make decisions on compared to other sports, partly because the number of data points is actually rather Smaller, you don't play that many innings and there is a huge element of luck that you're a perfectly good player. But due to some outrageous decision by the guy you're batting with, you might get yourself run out or there might be a brilliant catch and so on. And these things can. They will terminate your innings and make you look like you failed when you score when it wasn't your fault.

[Tim Harford]

Very good. Well, Rob, let me pin you down. Now, I'm not going to ask you to bet your life, you're going to bet your favourite slide rule out of the current England batting lineup, who's the man you would pick to go and score a century?

[Rob Eastaway]

I would pick Alistair Cook.

[Tim Harford]

And of current active world players, who would you pick?

[Rob Eastaway]

I would pick another captain, Michael Clark of Australia, who's in absolutely stupendous form and coming to this country next year.

[Tim Harford]

And of any player in history, Donald Bradman.

[Rob Eastaway]

He was stupendous. He scored 100 every fourth innings or less. He was incredible batsman, Rob Eastaway.

[Tim Harford]

And if, like Peter Harvey, you have a question, you can email us at More or lessbc. One of the most read articles on the Daily Telegraph's website this week was 2/3 of millionaires left Britain to avoid 50p tax rate. Now, the best estimate of the number of millionaires in this country is something like 750,000 people. So have half a million people really left the country over tax? Well, no. The story is actually about those who earn more than a million pounds a year, which is not the usual definition of a millionaire. And in the year before the new 50p higher rate came in, there were about 16,000 people who put on their tax return that they earned more than a million pounds a year. Later, with a new higher rate, that number had fallen by 2/3. So something's going on. And I asked Susan Spash of top tax accountants Blick Rothenberg, what she thought of the Telegraph story.

[Susan Spash]

The headline is slightly misleading, to say the least. I think that the numbers may well be accurate. In as much as 16,000 reported more than a million in the 2009-10 tax year and significantly lower in the following tax year. There may well have been people who left the United Kingdom. Indeed. But there are other ways of managing your income so that the million pounds that is declared on your tax return will alter year on year.

[Tim Harford]

So if tax on petrol is about to go up, you go to the petrol station, you fill up your tank before the tax comes in. Similarly, if tax on income is about to go up, you recognise your Income before the tax rate goes up.

[Susan Spash]

Yes. To bring your income into the 9, 10 year and pay perhaps 40% income tax, rather than wait and have it paid in the 10, 11 tax year and pay 50%.

[Tim Harford]

And we're talking about people who make a million pounds a year or more, you advise people who make a lot of money.

[Ruth Alexander]

We do.

[Tim Harford]

You think the bulk of these million pound earners who went missing, the bulk of them were tax planning. They didn't leave the country.

[Susan Spash]

They were tax planning. Yes. That would be my take on it.

[Tim Harford]

Accountant Susan Spash. This week, the Home Office floated the idea of a minimum price on alcohol of 45 pence per unit. Scotland will have a 50 pence minimum price from April. Just for context, a unit of alcohol is 10 millilitres of pure alcohol and there are about 10 units in a bottle of wine or about 3 units in a pint of lager, depending, of course, on the strength of the drinks in question. This proposal raises all sorts of intriguing questions. Would a minimum price affect the price of many drinks or just a few of the cheapest ones? What would be the impact on household budgets? And what would be the impact on alcohol consumption? I spoke to Andrew Lester, a senior research economist at the Institute for Fiscal Studies.

[Andrew Lester]

The Home Office has said that what it wants to do is reduce the availability of alcohol sold at very low or heavily discounted prices, which implies it would only hit a very small part of the market. But from our estimates, it looks like that almost 60% of alcohol units sold off license, so sold in supermarkets and off licenses, would be affected by a minimum price of 45p a unit. So it's a pretty big policy.

[Tim Harford]

And looking at the numbers you've sent through and put on your website, 85% of cider and Perry drinks would have to increase their price. 72% of lager. I mean, these are actually fairly substantial, aren't they?

[Andrew Lester]

Yes, these are fairly big numbers. Cider and perry tends to be the cheapest sort of alcohol, we think. On average, it sells for just over 31 pence per unit. So 45p would be quite a bit higher than that. But even for things like wine, it's just under half the market. 46% of wine units, for example, would be affected by the minimum price.

[Tim Harford]

Do we know anything about the distribution of the impact? And I suppose there are two ways to look at it. One is income distribution. Will poor households pay more? And the second is, will problem drinkers pay more? Do we know anything about that?

[Andrew Lester]

If we look by income, then we find that there's a slightly bigger impact on average, for poorer households, it equates to about 1.1% of the grocery spending of households with incomes below 10,000 pounds a year, about 0.5% of the spending of households with incomes above 60,000 pounds a year.

[Tim Harford]

And I suppose the big question, and this is not really the Institute for Fiscal Studies main area of expertise, the big question is whether it will discourage people from problematic drinking. Are you aware of any research into that?

[Andrew Lester]

There's an awful lot of research and an awful lot of evidence which demonstrates that when the price of alcohol goes up, people consume less of it. So I think we can be fairly confident that this policy is going to reduce drinking overall. What we don't necessarily know so clearly is whether it's the problem drinkers, perhaps the people who are addicted, or the people who are out binging, who will be reducing their consumption, particularly as a result of this. But I think it's a fairly safe bet that drinking will go down as a result of a minimum price.

[Tim Harford]

Andrew Lester of the Institute for Fiscal Studies, you're listening to More or Less, in association with the Open University. More or Less has been on air for a nice round 10 years now, and loyal listeners know that we don't shrink from tackling even the gnarliest of subjects. If there's a heated debate that would benefit from the light of statistics, we enter the fray. And that must be why loyal listener Martin McManus felt able to come to us with this weighty question. How many LEGO bricks stacked one on top of the other would it take

[Andrew Lester]

to destroy the bottom brick?

[Tim Harford]

Martin had seen the issue being pondered extensively on the website Reddit. And Ruth Alexander. He thought we might have something to add.

[Ruth Alexander]

Well, we do.

[Tim Harford]

We do indeed, don't we, Ruth? And we got straight onto our friends at the Open University Engineering department. And you'd have thought they didn't want to be bothered with such trivial questions.

[Ruth Alexander]

Yes. But in fact, they got the lab all fired up and invited me right on over.

[Tim Harford]

Excellent people they are.

[Ruth Alexander]

Lecturer Dr. Ian Johnston was at the vanguard.

[Dr. Ian Johnston]

That's an interesting question. I'm just surprised that I couldn't find the answer. When you first got in touch, my natural response was to say, well, just Google it. Crush strength of a LEGO brick. Somebody must have done it. To my surprise, I found a lot of speculation about what it is, but no clear evidence about what it is.

[Ruth Alexander]

How do we go about working this out?

[Dr. Ian Johnston]

There are several ways of approaching it, but the way I'm going to do it Today is we're going to find what load, what force is required to crush a LEGO brick, and then we're going to work out what mass that corresponds to sitting on top of the LEGO brick. A mass is not a force, but a mass produces a force because of gravity. Once we know that mass, and we know the mass of one LEGO brick, we know how many LEGO bricks we had to produce the right mass to produce the right force to crush the LEGO brick. This is a servo hydraulic testing machine. There's a hydraulic pump which runs a hydraulic ram pushing a plate upwards, on which we've got a LEGO brick sitting on top of that, there's another plate with a load cell on top, which measures the force on the LEGO brick as it's compressed. And because we're beginning to get a little bit nervous about the number of bits that might fly into and it's failing, we're setting it up to do it automatically so that we can all back out of the room, so that none of us is in range when the thing goes bang.

[Tim Harford]

This man is serious. I'm glad I've got my safety goggles on. So I'm just trying to picture this. There's this one poor little LEGO brick and it sat between these huge, gigantic metal plates.

[Ruth Alexander]

Yes. It was a 2x2 Lego brick. And the load on top of it got larger and larger and then. Wait for it. Nothing.

[Tim Harford]

Nothing.

[Ruth Alexander]

Well, not much.

[Dr. Ian Johnston]

Ah, it's folding. Oh, no, it isn't. I was looking at the nut at the top. It's not doing anything. Four and a half kilonewtons. We're just approaching half a ton now. It's hardly increasing anymore. It's more or less constant.

[Ruth Alexander]

What does that mean?

[Dr. Ian Johnston]

It means we've probably got a material failure and the material is just flowing out of the way now and not able to take it anymore.

[Tim Harford]

So no big bang moment?

[Ruth Alexander]

No, the brick just kind of melted.

[Tim Harford]

I'll take my goggles off then. How many LEGO bricks then, stacked one on top of the other, would it take to destroy this poor bottom brick?

[Ruth Alexander]

Well, Ian and the team did two more tests to be sure we hadn't just happened upon the strongest LEGO brick in existence. And in fact, they were impressed at the consistency of LEGO manufacture, I should say.

[Tim Harford]

Other plastic building kits are available, although

[Ruth Alexander]

LEGO is the best.

[Tim Harford]

Ruth, you're not allowed to say that. The final result is the average of

[Dr. Ian Johnston]

the three, which is pretty tightly clustered together, which gives me confidence, is 4,240 Newtons. That's equivalent to a mass on top of A thing of 432 kilograms, a 1.152 grams per brick, that's 375,000 bricks. A few more, but we'll ignore that it's experimental error, giving us a grand total height of 3591 meters.

[Tim Harford]

375,000 bricks over three and a half kilometers high. And that's what it would take to make that bottom brick crack, or rather ooze.

[Ruth Alexander]

Yes, a 2x2 brick. Ian reckons a 2x4 rectangular brick would fail sooner and a 1x2 brick could probably take a bit more.

[Tim Harford]

That's all very well. I'd like to meet a LEGO builder who could actually build a three and a half kilometer high tower. Actually, I really would like to meet a LEGO builder who could build a 3 1/2 kilometer high tower. Do you know any LEGO builders?

[Ruth Alexander]

Well, I do. In fact, Duncan Titmarsh from Bright Bricks is an official Lego builder.

[Tim Harford]

This man is certified. If he can't do it, no one can.

[Ruth Alexander]

Yes, that's what I thought. So I went to see him and his business partner, Ed diamond, at their warehouse where they were putting the finishing touches to a big Lego advent calendar for Covent Garden. Do you think it would be possible to build a structure that was three and a half kilometers high? No. I wish you could see people's faces on the radio because yours was a picture. Then.

[Rob Eastaway]

If you try stacking two by two bricks, as soon as you get beyond three or four metres tall, there's almost no way that you can take out all of the kinks and the loading and any amount of movement in the air. So it would be totally structurally impossible to do it.

[Tim Harford]

Whilst it's an interesting theory, official Lego builder Duncan Titmarsh and his business partner Ed diamond, and of course, Ruth Alexander. And that's all the weight of numbers we can bear this week. But please keep your questions and your comments piling in via more or lessbc.co.uk. we can take the pressure. Our website with articles and a downloadable version of this program is BBC.co.uk more or less until next week. Goodbye.

Thanks for listening to this download of More or Less. It was presented by Tim Harford, the Financial Times undercover economist. The producer was Wesley Stevenson. The editor was Richard Varden. And just in case you were wondering why an engineer came all the way down from Scotland to help us crush a Lego brick, here's why.

[Dr. Ian Johnston]

My mother is a retired maths teacher and she listens to More or Less every week and I think if this makes it to broadcast, she's going to think my entire career has been worthwhile. Thanks, Mum.