Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Nice riddle

Author: Ricardo Gibert

Date: 05:24:39 01/09/02

Go up one level in this thread


On January 09, 2002 at 06:54:35, Colin Frayn wrote:

>On January 07, 2002 at 20:24:01, Hans van der Zijden wrote:
>
>>I told a friend this riddle and she is still convinced that it doesn't matter if
>>you change or not. She agrees that you have 1/3 chance getting it right the
>>first guess, but after one (empty) door is opened she keeps saying there are 2
>>doors left, so now you have 1/2 chance if you stick to your choice. I try to
>>explain it to her in all the ways I could think of, but she is as stubborn as 3
>>mules. I also played this situation 30 times with and 30 times without changing.
>>She thinks I was lucky and the random die showed too many times the number 1.
>>Anyone an idea how to explain this to her.
>
>I tried to convince my dad of this and I ended up writing a program to run the
>test 1 million times, and sure enough, changing the door got about 2/3 correct.
>In fact, when I was writing the program, it became even more obvious that this
>was the correct answer and I found that, after optimisation, I was almost
>writing a program to print out "2/3".  I suggest you try the same and show your
>friend (but do it properly).
>
>Cheers,
>Col


http://mathforum.org/dr.math/faq/faq.monty.hall.html
http://www.stat.sc.edu/~west/javahtml/LetsMakeaDeal.html



This page took 0 seconds to execute

Last modified: Thu, 15 Apr 21 08:11:13 -0700

Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.