Welcome to the NavList Message Boards.

NavList:

A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Message:αβγ
Message:abc
Add Images & Files
    or...
       
    Reply
    Re: The Darn Old Cocked Hat - the sequel 1
    From: Tom Sult
    Date: 2013 Mar 17, 14:13 -0500
    This explanation is a commonly held view but I think it is in error. These are really two independent events. The first was a choice of three. The second was a nonrandom elimination  of one of the choices. This makes the second event an independent choice of one out of two. Therefore keeping your current curtain or changing to the other curtain results in the same 50-50 probability.

    If the move from the three curtain choice to the two curtain choice was a random event then the probabilities may well change. In the event that it were a random choice occasionally the world cruise would have been revealed and eliminated. This would've placed the likelihood of winning at zero. But because that is never an option in this scenario they are actually two independent throws of the "dice".

    Tom Sult
    Sent from my iPhone

    On Mar 17, 2013, at 13:17, Don Seltzer <timoneer{at}GMAIL.COM> wrote:


    Geoffrey replies:
    >But surely Don, once Monty has revealed that one of the doors does not hide the prize, there are only two doors left and we don't know behind which door the prize sits. So, regardless of which door was chosen first, the probability that the prize is behind each of the remaining two doors is then just 1/2, isn't it?

    If this is not the case, why not?
    >

    If Monty were making his pick blindly, I would agree that the odds had become 50/50. But his pick is not random and there is always an empty curtain for him to deliberately choose. Nothing he has done has altered the 1/3 probability of my initial choice being correct. But Monty has eliminated one of the alternate choices.

    My first pick remains at 1/3 chance of being correct, which means the remaining curtain must have a 2/3 chance of being the big prize.

    Don Seltzer


    ----------------------------------------------------------------
    NavList message boards and member settings: www.fer3.com/NavList
    Members may optionally receive posts by email.
    To cancel email delivery, send a message to NoMail[at]fer3.com
    ----------------------------------------------------------------

    View and reply to this message: http://fer3.com/arc/m2.aspx?i=122905

       
    Reply
    Browse Files

    Drop Files

    NavList

    What is NavList?

    Join NavList

    Name:
    (please, no nicknames or handles)
    Email:
    Do you want to receive all group messages by email?
    Yes No

    You can also join by posting. Your first on-topic post automatically makes you a member.

    Posting Code

    Enter the email address associated with your NavList messages. Your posting code will be emailed to you immediately.
    Email:

    Email Settings

    Posting Code:

    Custom Index

    Subject:
    Author:
    Start date: (yyyymm dd)
    End date: (yyyymm dd)

    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site