Last week somebody in Horsham bought a lottery ticket at Waitrose in Piries Place and won £2.3 million.  This week, if the papers are to be believed, business has been booming for the Waitrose lottery machine as people have been flocking to buy a ticket from the ‘lucky shop’.  Which part of “random” is it that people don’t understand?

While I would love to see someone from Horsham win again this week (although not as much as I would like to see someone from my house win it) it isn’t very likely.  The winning ticket is not more likely to be bought at Waitrose just because one of last week’s winning tickets was bought there.

On the other hand – it is no less likely either.  That is the point of random:it can be very counter-intuitive.  Everything about the draw makes the results of any week totally independent of previous weeks, in the same way that if you toss a coin 10 times the chances of getting heads on the 10th go are 50% even if the previous 9 were all tails, or if they were all tails.

You can’t just point at a statistic that says no shop has ever sold a winning ticket two weeks in a row and say that the shop selling last week’s winner is guaranteed to not do the same this week.  Whatever numbers you choose, or are chosen for you on a lucky dip, and wherever you buy a ticket, you have the same millions-to-one odds against winning.  That’s what random means.  You can’t study the form like with horse racing. In fact the only way to improve your own personal odds is to buy more tickets, but each one you buy will have an equal (and tiny) chance of winning.

But that is no reason not to have a go, as long as you really don’t expect to win.  Some recent research showed that many punters get far more than a pound’s worth of enjoyment out of their losing tickets.  Apparently the day dreaming about what one would do with the jackpot has some sort of positive effect.

There is one little superstition regarding lottery tickets that I will own up to myself though.  Somebody did the maths and worked out that if you buy a ticket earlier in the week you are statistically more likely to die in a road accident than to win, so you won’t catch me buying a ticket days in advance.