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Can you count the packets of crisps?

People giving out crisps
Image caption What do the crisps say?

Terrified of numbers? In his regular Go Figure column, Michael Blastland explains how a bit of creative thinking can help.

Have you got the brain for statistics? Here's all it takes.

Numbers. What you see is not always what you get. So this week, Go Figure offers a quick and easy game to train the brain to unpick data.

Outside London's King's Cross Station, just before the election, I snapped a crisp company seeking publicity and giving away packets coloured red, blue and yellow, with the main party leaders on the front.

Look closely and you can see a half-empty bin for Nick Clegg, a bin full-to-overflowing for Gordon Brown, with David Cameron somewhere in the middle. Ostensibly, the data (how many crisp packets are in each bin) tells us which party, or party leader, was most popular at the time.

Here's the game: give as many reasons as you can why the data might lie. Not saying it does, or did, just asking you to imagine that it might. We'll show the most inventive below.

The point is not to compete with all those mammoth end-of-year quizzes for difficulty. This isn't hard. And that's the point, but it can be creative.

Number junk

Many people are terrified of numbers. Clever people - and newspapers and politicians - say outrageously daft things, often, with them and about them.

But making a start on teasing numbers apart is often no harder than dreaming up the stories that might explain why what we see is not what we get. A little creative scepticism goes a long way. One secret to being at ease with stats - believe it or not - is imagination.

Image caption The party political crisps - which one would you eat?

Counting crisp packets and working out what the number means turns out to be not so very different from counting migrants, crime, hospital mortality rates, flu cases or numerous other everyday news numbers.

Take one potential explanation for the crisps: that the Brown bin has just been refilled from the boxes behind (whether true or not). It's a point about the difference between stock and flow, a principle that matters hugely to measuring and understanding the length of a hospital waiting list, for example.

If the list is long but people on it are flowing fast, it might not matter that it's long: an easy concept, occasionally mangled in political argument.

So the question to all those who routinely murder numbers from a failure to think about them properly is - can you count packets of crisps? And the reassurance to those of us who have to wade through the number junk is that anyone can make a start - with a little imagination.

Who's got it?