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Winning the Lottery
Probability and co-incidence
It is human nature to look for the positive outcome in a situation. In a world of chance this can skew our perceptions.
Maths helps to put probability and chance into perspective. We spoke to experts about some of the real explanations of chance and luck.
Winning the lottery
Maths and the money market
Travel and traffic
Nature, beauty and maths
Magic numbers
What are my chances?
Audio Available Lottery logic
What is it about lotteries that makes us take a punt despite the phenomenal odds against us winning?

Psychologist, Mark Griffiths, has been investigating why people are so attracted to lotteries.

  He says that people are drawn in by the huge amount they can win. Lotteries require a low stake and you could potentially win millions of pounds.  
  When people buy a lottery ticket they don't think about the actual chances of winning, they think of the money they could win.  
  He also believes that people tend to overestimate the chance of something good happening to them even if the odds are infinitesimal whereas people often underestimate the chance of something bad occurring.  
  "If you were told that you have a one in fourteen million chance of getting cancer in the next seven days people will say 'oh well it is obviously not going to happen to me it is so infinitesimal' but the fact that there is a one in fourteen million chance of winning the lottery people think 'yes, it's got to be someone why can't it be me'"  
Audio Available I was so close...
If you buy a ticket for the lottery that has the number 37 on it and the number 38 is drawn, you think, "I was so close..." BUT were you?
Mark Griffiths says
the psychology of the near miss is particularly well known in the gaming industry.
  When people pick a number they attach some sort of value to it. If you pick the number 9 and the number 8 or number 10 shows up you can think you have a near miss or if the number 29 or 39 turns up you could perceive it as a near miss. Some people will even interpret a number 6 as an upside down nine and consequently a near miss.  
  So much potential is very reinforcing and makes people want to try again.  
  Mark thinks that people do not really understand the odds of the lottery. They don't understand that each number retains the same chance of winning no matter how many draws take place.  
  In a recent survey 21% of people thought that if they put the same numbers on to the lottery for the rest of their lives that they would have a chance of winning. The reality is they would have to put the same numbers on 135 000 years before they would have an evens chance of winning.  
"People really don't understand what it means to have a one-in-a-14-million chance. People have no idea how big 14 million is."
  Audio Available Chance and numbers  
  If I tell you the chance of your toe operation going wrong is 6%, are you worried?
Sounds pretty low doesn't it.
  If I tell you that the odds of failure are 1 in 16, how does that affect your perception of the risk involved?  
  In actual fact, these figures both mean that you have a 94% chance of success. Maths helps to get everything in perspective, to assess risk logically.  
The reality of chance
Audio Available What a co-incidence!
"I've got Mickey mouse socks on and so have you..."
Is this a co-incidence?
  According to Professor Ian Stewart We live in a world where there are so many things going on that every so often you are going to find a couple of them that match.  

He says we notice these co-incidences because our minds have evolved to do so.

  "Millions of years ago when we were out on the african plains, it was very important to size up a situation quickly and take a decision. If you saw a flash of orange behind a rock, you couldn't say 'oh it might be a lion', of course it might not be a lion... at that point the lion would have leapt on you, if you say 'Ah! Lion!' and run you are still alive."  
Audio Available Most of the children fathered by Israeli pilots are girls
Isn't that amazing but what's the explanation?
As a reproductive biologist Dr Jack Cohen was asked to find an explanation for this phenomenon.
"I've no idea what the explanation is but I'll make a prediction from now on it will be 50/50."
  He believes the answer is not a biological one but one of mathematics and random data. The theory is that if you look back over any kind of history there are going to be little clumps of irrational occurences.
  For example you might find that at some point in time all the wives of Israeli airline pilots were blue eyed but this would just be one of the clumps in random data that you are going to get. This is because random data isn't spread out evenly, it occurs in clumps.  
Audio Available Jack predicts a co-incidence
What puts the co-incidences that have happened in perspective are all the ones that MIGHT have happened. Ian Stewart and Jack Cohen took a trip to Sweden in search of a near co-incidence.
  Jack began by predicting that there would be a co-incidence. He predicted that they would meet someone they knew at Arlanda Airport in Stockholm.  
  Sure enough they ran into a colleague of theirs called Stefano at the airport information desk. This was their co-incidence but what if Stefano had been going through exactly the same airport but on a different day or even an hour later, or what if he hadn't gone to the information desk. They wouldn't have noticed it.  
"All the things that just miss must be much more common than the things that actually happen."
  To prove their theory what Jack and Ian needed was a co-incidence that might have happened but didn't.  
  Two weeks later, they were telling a friend called Ted about their airport experience. Ted asked which hotel they had stayed in? Then he asked which day they had stayed there. Bingo! Ted revealed that he had been in the same hotel a day later. Ted being in the same hotel in Stockholm on the same day as Jack and Ian was the co-incidence that almost happened but didn't!  
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