“Lies, damn lies, and statistics”

Ours is the age of statistics; of number-crunching, of quantifying, of defining everything by what it means in terms of percentages and comparisons. Statistics crop up in every walk of life, to some extent or other, in fields as widespread as advertising and sport. Many people’s livelihoods now depend on their ability to crunch the numbers, to come up with data and patterns, and much of our society’s increasing ability to do awesome things can be traced back to someone making the numbers dance.

In fact, most of what we think of as ‘statistics’ are not really statistics at all, but merely numbers; to a pedantic mathematician, a statistic is defined as a mathematical function of a sample of data, not the whole ‘population’ we are considering. We use statistics when it would be impractical to measure the whole population, usually because it’s too large, and when we instead are trying to mathematically model the whole population based on a small sample of it. Thus, next to no sporting ‘statistics’ are in fact true statistics as they tend to cover the whole game; if I heard during a rugby match that “Leicester had 59% of the possession”, that is nothing more than a number; or, to use the mathematical term, a parameter. A statistic would be to say “From our sample [of one game] we can conclude that Leicester control an average of 59% of the possession when they play rugby”, but this is quite evidently not true since we couldn’t extrapolate Leicester’s normal behaviour from a single match. It is for this reason that complex mathematical formulae are used to determine the uncertainty of a conclusion drawn from a statistical test, and these are based on the size of the sample we are testing compared to the overall size of the population we are trying to model. These uncertainty levels are often brushed under the carpet when pseudoscientists try to make dramatic, sweeping claims about something, but they are possibly the most important feature of modern statistics.

Another weapon for the poor statistician can be the mis-application of the idea of correlation. Correlation is basically what it means when you take two variables, plot them against one another on a graph, and find you get a nice neat line joining them, suggesting that the two are in some way related. Correlation tends to get scientists very excited, since if two things are linked then it suggests that you can make one thing happen by doing another, an often advantageous concept, and this is known as a causal relationship. However, whilst correlation and causation are rarely not intertwined, the first lesson every statistician learns is this; correlation DOES NOT imply causation.

Imagine, for instance, you have a cold. You feel like crap, your head is spinning, you’re dehydrated and you can’t breath through your nose. If we were, during the period before, during and after your cold, to plot a graph of one’s relative ability to breath through the nose against the severity of your headache (yeah, not very scientific I know), these two facts would both correlate, since they happen at the same time due to the cold. However, if I were to decide that this correlation implies causation, then I would draw the conclusion that all I need to do to give you a terrible headache is to plug your nose with tissue paper so you can’t breath through it. In this case, I have ignored the possibility (and, as it transpires, the eventuality) of there being a third variable (the cold virus) that causes both of the other two variables, and this is very hard to investigate without poking our head out of the numbers and looking at the real world. There are statistical techniques that enable us to do this, but they are for another time.

Whilst this example was more childish than anything, mis-extrapolation of a correlation can have deadly consequences. One example, explored in Ben Goldacre’s Bad Science, concerns beta-carotene, an antioxidant found in carrots, and in 1981 an epidemiologist called Richard Peto published a meta-analysis (post for another time) of a series of scientific studies that suggested people with high beta-carotene levels showed a reduced risk of cancer. At the time, antioxidants were considered the wonder-substance of the nutrition, and everyone got on board with the idea that beta-carotene was awesome stuff. However, all of the studies examined were observational ones; taking a lot of different people, seeing what their beta-carotene levels were and then examining whether or not they had cancer or developed it in later life. None of the studies actually gave their subjects beta-carotene and then saw if that affected their cancer risk, and this prompted the editor of Nature magazine (the scientific journal in which Peto’s paper was published) to include a footnote reading:

Unwary readers (if such there are) should not take the accompanying article as a sign that the consumption of large quantities of carrots (or other dietary sources of beta-carotene) is necessarily protective against cancer.

The editor’s footnote quickly proved a well-judged one; a study conducted in Finland some time afterwards actually gave participants at high risk of lung cancer beta-carotene and found their risk of both getting the cancer and of death were higher than for the ‘placebo’ control group. A later study, named CARET (Carotene And Retinol Efficiency Trial), also tested groups at a high risk of lung cancer, giving half of them a mixture of beta-carotene and vitamin A and the other half placebos. The idea was to run the trial for six years and see how many illnesses/deaths each group ended up with; but after preliminary data found that those having the antioxidant tablets were 46% more likely to die from lung cancer, they decided it would be unethical to continue the trial and it was terminated early. Had the Nature article been allowed to get out of hand before this research was done, then it could have put thousands of people who hadn’t read the article properly at risk; and all because of the dangers of assuming correlation=causation.

This wasn’t really the gentle ramble through statistics I originally intended it to be, but there you go; stats. Next time, something a little less random. Maybe

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Poverty Changes

£14,000 is quite a large amount of money. Enough for 70,000 Freddos, a decade’s worth of holidays, two new Nissan Pixo’s, several thousand potatoes or a gold standard racing pigeon. However, if you’re trying to live off just that amount in modern Britain, it quickly seems quite a lot smaller. Half of that could easily disappear on rent, whilst the average British family will spend a further £4,000 on food (significantly greater than the European average, for one reason or another). Then we must factor in tax, work-related expenses, various repair bills, a TV license, utility & heating bills, petrol money and other transport expenses, and it quickly becomes apparent that trying to live on this amount will require some careful budgeting. Still, not to worry too much though; it’s certainly possible to keep the body and soul of a medium sized family together on £14k a year, if not absolutely comfortably, and in any case 70% of British families have an annual income in excess of this amount. It might not be a vast amount to live on, but it should be about enough.

However, there’s a reason I quoted £14,000 specifically in the figure above, because I recently saw another statistic saying that if one’s income is above 14 grand a year, you are one of the top 4% richest people on planet Earth. Or, to put it another way, if you were on that income, and were then to select somebody totally at random from our species, then 24 times out of 25 you would be richer than them.

Now, this slightly shocking fact, as well as being a timely reminder as to the prevalence of poverty amongst fellow members of our species, to me raises an interesting question; if £14,000 is only just about enough to let one’s life operate properly in modern Britain, how on earth does the vast majority of the world manage to survive at all on significantly less than this? More than 70% of the Chinese population (in 2008, admittedly; the rate of Chinese poverty is decreasing at a staggering rate thanks to its booming economy) live on less than $5 a day, and 35 years ago more than 80% were considered to be in absolute poverty. How does this work? How does most of the rest of the world physically survive?

The obvious starting point is the one stating that much of it barely does. Despite the last few decades of massive improvement in the living standards and poverty levels in the world in general,  the World Bank estimates that some 20% of the world’s populace is living below the absolute poverty line of surviving on less than $1.50 per person per day, or £365 a year (down from around 45% in the early 1980s- Bob Geldof’s message has packed a powerful punch). This is the generally accepted marker for being less than what a person can physically keep body and soul together on, and having such a huge proportion of people living below this marker tends to drag down the global average. Poverty is something that the last quarter of the century has seen a definitive effort on the part of humanity to reduce, but it’s still a truly vast issue across the globe.

However, the main contributing factor to me behind how a seemingly meagre amount of money in the first world would be considered bountiful wealth in the third is simply down to how economics works. We in the west are currently enjoying the fruits of two centuries of free-market capitalism, which has fundamentally changed the way our civilisation functions. When we as a race first came up with the concept of civilisation, of pooling and exchanging skills and resources for the betterment of the collective, this was largely confined to the local community, or at least to the small-scale. Farmers provided for those living in the surrounding twenty miles or so, as did brewers, hunters, and all other such ‘small businessmen’, as they would be called today. The concept of a country provided security from invasion and legal support on a larger scale, but that was about it; any international trade was generally conducted between kings and noblemen, and was very much small scale.

However, since the days of the British Empire and the Industrial Revolution, business has got steadily bigger and bigger. It started out with international trade between the colonies, and the rich untapped resources the European imperial powers found there, moved on to the industrial scale manufacture of goods, and then the high-intensity sale of consumer products to the general population. Now we have vast multinational companies organising long, exhaustive chains of supply, manufacture and retail, and our society has become firmly rooted in this intense selling international economy. Without constantly selling vast quantities of stuff to one another, the western world as we know it simply would not exist.

This process causes many side effects, but one is of particular interest; everything becomes more expensive. To summarise very simply, the basic principle of capitalism involves workers putting in work and skill to increase the value of something; that something then gets sold, and the worker then gets some of the difference between cost of materials and cost of sale as a reward for their effort. For this to work, then one’s reward for putting in your effort must be enough to purchase the stuff needed to keep you alive; capitalism rests on the principle of our bodies being X% efficient at turning the food we eat into the energy we can use to work. If business is successful, then the workers of a company (here the term ‘workers’ covers everyone from factory floor to management) will gain money in the long term, enabling them to spend more money. This means that the market increases in size, and people can either sell more goods or start selling them for a higher price, so goods become worth more, so the people making those goods start getting more money, and so on.

The net result of this is that in an ‘expensive’ economy, everyone has a relatively high income and high expenditure, because all goods, taxes, land, utilities etc. cost quite a lot; but, for all practical purposes, this results in a remarkably similar situation to a ‘cheap’ economy, where the full force of western capitalism hasn’t quite taken hold yet- for, whilst the people residing there have less money, the stuff that is there costs less having not been through the corporation wringer. So, why would we find it tricky to live on less money than the top 4% of the world’s population? Blame the Industrial Revolution.

The President Problem

As one or two of you may have noticed, our good friends across the pond are getting dreadfully overexcited at the prospect of their upcoming election later this year, and America is gripped by the paralyzing dilemma of whether a Mormon or a black guy would be worse to put in charge of their country for the next four years. This has got me, when I have nothing better to do, having the occasional think about politics, politicians and the whole mess in general, and about how worked up everyone seems to get over it.

It is a long-established fact that the fastest way for a politician to get himself hated, apart from murdering some puppies on live TV, is to actually get himself in power. As the opposition, constantly biting at the heels of those in power, they can have lots of fun making snarky comments and criticisms about their opponent’s ineptitude, whereas when in power they have no choice but to sit quietly and absorb the insults, since their opponents are rarely doing anything interesting or important enough to warrant a good shouting. When in power, one constantly has the media jumping at every opportunity to ridicule decisions and throw around labels like ‘out of touch’ or just plain old ‘stupid’, and even the public seem to make it their business to hate everything their glorious leader does in their name. Nobody likes their politicians, and the only way for them once in power is, it seems, down.

An awful lot of reasons have been suggested for this trend, including the fact that we humans do love to hate stuff- but more on that another time, because I want to make another point. Consider why you, or anyone else for that matter, vote for your respective candidate during an election. Maybe it’s their dedication to a particular cause, such as education, that really makes you back them, or maybe their political philosophy is, broadly speaking, aligned with yours. Maybe it’s something that could be called politically superficial, such as skin colour; when Robert Mugabe became Prime Minister of Zimbabwe in 1980 it was for almost entirely that reason. Or is it because of the person themselves; somebody who presents themselves as a strong, capable leader, the kind of person you want to lead your country into the future?

Broadly speaking, we have to consider the fact that it is not just someone’s political alignment that gets a cross next to their name; it is who they are. To even become a politician somebody needs to be intelligent, diligent, very strong in their opinions and beliefs, have a good understanding of all the principles involved and an active political contributor. To persuade their party to let them stand, they need to be good with people, able to excite their peers and seniors, demonstrate an aligning political philosophy with the kind of people who choose these things, and able to lay everything, including their pride, in pursuit of a chance to run. To get elected, they need to be charismatic, tireless workers, dedicated to their cause, very good at getting their point across and associated PR, have no skeletons in the closet and be prepared to get shouted at by constituents for the rest of their career. To become a leader of a country, they need to have that art mastered to within a pinprick of perfection.

All of these requirements are what stop the bloke in the pub with a reason why the government is wrong about everything from ever actually having a chance to action his opinions, and they weed out a lot of people with one good idea from getting that idea out there- it takes an awful lot more than strong opinions and reasons why they will work to actually become a politician. However, this process has a habit of moulding people into politicians, rather than letting politicians be people, and that is often to the detriment of people in general. Everything becomes about what will let you stay in power, what you will have to give up to allow you to push the things you feel really strong for, and how many concessions you will have to make for the sake of popularity, just so you can do a little good with your time in power.

For instance, a while ago somebody compiled a list of the key demographics of British people (and gave them all stupid names like ‘Dinky Developers’ or whatever), expanded to include information about typical geographical spread, income and, among other things, political views. Two of those groups have been identified by the three main parties as being the most likely to swing their vote one way or the other (being middle of the road liberal types without a strong preference either way), and are thus the victim of an awful lot of vote-fishing by the various parties. In the 2005 election, some 80% of campaign funding (I’ve probably got this stat wrong; it’s been a while since I heard it) was directed towards swinging the votes of these key demographics to try and win key seats; never mind whether these policies were part of their exponent’s political views or even whether they ever got enacted to any great degree, they had to go in just to try and appease the voters. And, of course, when power eventually does come their way many of their promises prove an undeliverable part of their vision for a healthier future of their country.

This basically means that only ‘political people’, those suited to the hierarchical mess of a workplace environment and the PR mayhem that comes with the job, are able to ever get a shot at the top job, and these are not necessarily those who are best suited to get the best out of a country. And that, in turn means everybody gets pissed off with them. All. The. Bloody. Time.

But, unfortunately, this is the only way that the system of democracy can ever really function, for human nature will always drag it back to some semblance of this no matter how hard we try to change it; and that’s if it were ever to change at all. Maybe Terry Pratchett had it right all along; maybe a benevolent dictatorship is the way to go instead.