Re: Deal or no Deal

zcx wrote:
"John Dean" <john-dean@xxxxxxxxxxxxxxxx> wrote in message
news:dtn9ig$itf$1@xxxxxxxxxxxxxxxxxxxxxxx

The probability from the beginning of the game, before any boxes are
opened, is 0.5 that you have been allocated a blue box and 0.5 that
you have been allocated a red one. This probability doesn't change
no matter what happens in the course of the game.

So if you have two red boxes left, the probability that you have a
blue box is 0.5?

Yeah. Weird, innit? You have to distinguish between the probability (which is set by the way the boxes are originally allocated) and the reality (about which you may get more information as the boxes are opened).
Try it with a set of playing cards - 11 red and 11 black. Pick one at random (face down). The probability it is black is 0.5
Draw cards from the remaining 21 one at a time and examine them. What, in this process, could change the probability that you have a black card?
Repeat the process a thousand times. In roughly 500 of the experiments you will have a black card. In roughly 500 you will have a red card. The probability you had a black card is shown to be 0.5
BTW, if you don't like this explanation, is there any chance you're free for the Friday night card school round at mine?
--
John Dean
Oxford

.

Relevant Pages

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    (uk.media.tv.misc)
  • Re: Deal or no Deal
    ... reality (about which you may get more information as the boxes are ... The probability it is black is 0.5 ... the less likely that the card you have is ... they came from a pack with equal reds and blacks and ...
    (uk.media.tv.misc)