“‘You are on a game show on television. On the game show the idea is to win a car as a prize. The game show host shows you three doors. He says that there is a car behind one of the doors and there are goats behind the other two doors, He asks you to pick a door. You pick a door but the door is not opened. Then the game show host opens one of the doors you didn’t pick to show a goat (because he knows what is behind the doors). Then he says that you have one final chance to change your mind before the doors are opened and you get a car or a goat. So he asks you if you want to change your mind and pick the other unopened door instead. What should you do?’
Marilyn vos Savant (who was said to have the highest IQ in the world) said that you should always change and pick the final door because the changes are 2 in 3 that there will be a car behind that door.
But if you use your intuition you think that chance is 50-50 because you think there is an equal change that the car is behind any door.Lots of people wrote to the magazine to say that Marilyn vos Savant was wrong, even when she explained very carefully why she was right.
Firstly, you can do it by maths
The second way you can work it out is by making a picture of all the possible outcomes (posted above)
So if you change, 2 times out of 3 you get a car. And if you stick, you only get a car 1 time out of 3.
And this shows that intuition can sometimes get things wrong. And intuition is what people use in life to make decisions. But logic can help you work out the right answer.”–Mark Haddon, The Curious Incident of the Dog in the Night-time
I read this the other day and have been thinking about it ever since, so I thought I would share. I highly suggest you go read that book as soon as you can, it won’t take long to finish,
