Never Quote Percentages without Context
If I offered you 30 per cent of my apple pie would you want to know what type of pie I have? Or how big that pie might be? Type of crust? My question would make no sense because percentages, in and of themselves, mean nothing.
Percentages as used in Tim Worstall’s DRC Article
Percentages are the gift of the gab in any conversation. More often than not they are intentionally placed into reports and papers to obfuscate, trivialise or gazump an argument. Furthering my recent article along these lines, a sentence from The Register’s Rocks, hard places and Congo Minerals, provided by duckrabbitblog on Twitter a few days ago, reads:
We can however tell where coltan comes from, as a result of this project [5]. (Ignore their estimate that 50 per cent of the world’s Ta comes from DRC: it’s more like eight per cent.)Tim Worstall, The Register
Does that mean that 50 per cent of the world’s Ta coming from the DRC geographic area is unacceptable but that 8 per cent is somehow acceptable? How would we know? Nobody gave us the context. Nobody took the time to tell us how much actual Ta comes out of the region.
I’m surprised the editorial staff at The Register didn’t pick up on this question – Yes but what does 8 per cent mean? More important still, it hangs like a beacon asking about the provinence of that 8 per cent assertion as though it was a commonly accepted fact in The Register’s general readership. This leaves two logical assertions… group A blatantly lied about 50 per cent (a story in itself)… or that group A and group B find the number difficult to quantify and they have both made assertions based on fuzzy data.
Percentages Trivialise and Obfuscate the Truth
The problem is that percentages lack context and are most often used to trivialise or obfuscate the truth. If you’re a journalist or a researcher the use of percentages should ring warning bells about the intentions and knowledge of the author. No disparity directly on Tim Worstall, this is a common problem with throwing percentages into an article… so easy to slip them under the door and run without having to justify or elaborate on the context.
Percentages allow little more than a trivialised 2 dimensional pie chart… they’re a tool of bluster and boondoggle reportage.
OK lets put it this way… is 1 per cent of my cup of coffee the same as 1 per cent of the arable land in China? Is 30 per cent of your bank account comparable to 30 per cent of anybody else’s bank account?
And the beauty of percentages is their ability to trivialise… there were only 2 per cent livestock losses after recent floods can make 10,000 sheep dead in the fields sound like it’s around 10 sheep.
Percentage by itself is Meaningless
So back to the snippet above, simply because it’s a recent example of non-contextualised obfuscating large numbers into 2 dimensional pie charts… do you think 8 per cent of the cars on the road is an insignificant number? What about 8 per cent of the news articles written globally? In China? In Tibet? See, no context.
All I’m saying is that if you’re out to prove a point in an article (or any argument) the first black-hat trick is to pronounce uncontextualised percentages. The next is to push a percentage out that is under 15%… “oh it’s only 2 per cent of people who are going to be robbed on the train”… well, you should see the pattern.
It’s no different than showing me statistics as individual facts… what do they mean? Perhaps 8 per cent of world Ta is a fucking lot of trade Mr Worstall. Like 5 per cent of the web browsers currently accessing the World Wide Web with JavaScript disabled. How many people would that represent nowdays? A lot? But [sarcastically] it’s only 5 per cent, right? And I wouldn’t mind .0001% of the money Wal-Mart spends on its logistics capability… whatever that means.
The point is that percentages sound great as you fly past them in consumption mode but ALWAYS stop and smell those roses. Ask yourself what they really mean.
