Bill Graham wrote:
Arny Krueger wrote:
"William Sommerwerck" wrote in
message

After you know there is a goat behind door #3 and are
given a chance to guess again, there is a 50% chance the
car is behind door #1 and a 50% chance the car if behind
door #2. Change your choice or not, you have a 50%
chance of being right.

This is not correct. I explained it in a previous post.

You seriously think I didn't read your alleged explanation?

You've been known to be wrong before... ;-)

Like this...

Because you will have initially selected the wrong door
2/3 of the time (right?) it follows that 2/3 of the time
the good prize will be behind one of the two other doors.
The host will /always/ select a door with a goat,
therefore, you should switch, because there's a 2/3
chance the other door will have the good prize.

That is sheerist ********.

Your first mistake is assuming that there is a connection between
your 2 guesses. In fact you have been given two different and
disconnected games to play.

Other than the fact that the car and 1 goat are carries-over from the
first game, there is no connection. If they brought in another car
and another goat, then the odds during the second game would be the
same.
When you play the second game your odds of winning have improved to
1/2. You have 1 chances out of 2, no more, no less to win when there
are 2 opportunities.

Pick whichever door you will, unless you can smell the goat! ;-)

It would appear to me that the real purpose of this thread is to test
the gullibility of people.

But by not switching doors, you are ignoring the new information that
the prize has to be behind one of the other two doors.... You are
sticking with your original guess that had only a 1/3 chance of being
right. By switching doors, you are including the new information that
the prize has to be behind one of the other two doors, and your new
chance of winning is 50%
IOW, lets suppose that you picked door #1 and then left the game,
went home, and waited by the phone to find out whether you won or
not. There is only a 1/3 chance of your getting the lucky call.

But by staying on board, and switching your guess to door #2, you are
taking advantage of the "new game" that has a 50% chance of
success........

Another way to look at it is, you are allowed to play the game twice. If you
only play it once, your chance of winning is only 1/3 and you can't play
again. But if you accept a loss in the first game, then they will let you
play again with a 50% chance of winning. So, you are better off by accepting
a loss in the first game, and then getting to play the game again with a 50%
chance of winning in the second game.