Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: New and final solution of the Monty Hall Dilemma *Conclusion*

Author: Rolf Tueschen

Date: 02:50:42 09/27/02

Go up one level in this thread


On September 26, 2002 at 18:14:03, Sune Fischer wrote:

>On September 26, 2002 at 18:00:12, Uri Blass wrote:
>
>>On September 26, 2002 at 17:06:21, Sune Fischer wrote:
>>
>>>On September 26, 2002 at 16:42:37, Uri Blass wrote:
>>>
>>>>On September 26, 2002 at 16:14:46, Sune Fischer wrote:
>>>>
>>>>>On September 26, 2002 at 15:30:42, Rolf Tueschen wrote:
>>>>>>
>>>>>>You are wrong because we had only one question. Was Marilyn right for the exact
>>>>>>text of the question. I said no, because the question did not make clear that
>>>>>>the host must _always_ open a door.
>>>>>
>>>>>What question are you refering too, not this one surely:
>>>>>"Suppose you're on a game show, and you're given a choice of three doors. Behind
>>>>>one door is a car; behind the others, goats. You pick a door-;say No. 1-;and the
>>>>>host, who knows what's behind the doors, opens another door-;say No. 3-;which
>>>>>has a goat. He then says to you, “Do you want to pick door No. 2?” Is it to your
>>>>>advantage to switch your choice? "
>>>>>
>>>>>Not only does it say he opens a door, it also says he knows what is behind the
>>>>>doors, and that he will open one with a goat, clearly he is all-knowing.
>>>>
>>>>The question says that the host knows.
>>>>The question does not say that he always must open a door.
>>>
>>>Yes it does:
>>>"the host, who knows what's behind the doors, opens another door-;say No. 3-;"
>>
>>This is only explanation of what happened.
>>The only information that is clear from the question is:
>>1)you play on a game when you choose a door.
>>2)The host knows what is behind the doors.
>>3)The host opened a door that is the wrong door.
>>
>>This information is not enough to decide if you should switch doors.
>>
>>It is possible to understand that the host has to open a wrong door but it is
>>not clear from the question.
>>
>>The question only says:
>>"host, who knows what's behind the doors, opens another door-;say No. 3-;which
>>has a goat"
>>
>>If his strategy is always to open a door is not clear from the question and the
>>only information that we know for sure is that he opened a door.
>
>Yes you can, what is being described to you is an algorithm of how the show will
>proceed/the rules of the game:
>
>1)you play on a game where you choose a door.
>2)The host knows what is behind the doors.
>3)The host will open a door that hides a goat.
>4)You now have to decide if you want to switch doors.
>
>>The question did not use past tense but present tense so it makes the impression
>>that the host always opens a door so I cannot say that merilyn was wrong but it
>>is not clear from the question so I cannot say that people who say that data is
>>missing are wrong.
>
>I don't see anything unclear about the question at all, he opens a door for
>sure, and more than that, he opens a door with a goat behind it, he can do this
>because he knows what the doors hide, there is no need for past tense, this guy
>can see into the future!

Very interesting to observe how people argue. In special the methods to prove
something that should be proved. That alone already justified the topic here in
the computer chess surroundings. Because it's IMO a traditional weakness in the
debates about 'strength', ranking lists and 'confidence intervals'.

Here in the debate between Uri and Sune the problem becomes very clear. People
have a tendence to prove as true what they think to be true. But that proves
nothing but weak education in science.

 - Uri makes very clear: "host, who knows what's behind the doors, opens another
door" - this is exactly what the original question of Mr. Whitaker said. So,
correctly, Uri makes the conclusion: "This information is not enough to decide
if you should switch doors. It is possible to understand that the host has to
open a wrong door but it is not clear from the question. - If his strategy is
always to open a door is not clear from the question and the only information
that we know for sure is that he opened a door."

Uri does what every scientist must do, he tries to find the parts of data that
could be accepted _without_ a doubt. Because all the rest might contain
interesting data, but it can't be taken with certainty.


- Sune on the other side has a tendence for authoritarian declarations, where
the certainty is a question of imperative gesture but not of content: "I don't
see anything unclear about the question at all, he opens a door for sure, and
more than that, he opens a door with a goat behind it."


Moral

We should at least try hard to do a thorough analysis of the situation and the
commentaries before we give our own opinions. It's so vain to state something
with shallow content when the description of the situation could not be
understood, because it can be easily reveiled.

(Although I must admit that the whole thread was discussed without a single
insult or offense. And I want to thank everybody. Let's give a short verdict.
Marilyn was wrong because she didn't answer exactly the question of Mr.
Whitaker. Probably she was influenced by the practice in the named show. But
Monty, the host, stated that he was _not_ forced to open a door. So the
question, if a candidate could make a logical choice with advantageous chances,
must be answered with 'No!'. Therefore I insisted on the importance of the
psychological situation of the candidate and not the picture as viewed from the
outside, or after a simulation, because the candidate had only a single unique
occasion to make his choice. In his view the opening of a door simply reduced
the alternatives and led to a chance of 1/2 for both doors. In special the
candidate could _not_ know if the host had opened a further door because he knew
that no car was behind it. The text of the question does not allow to make a
different conclusion. QED)

Rolf Tueschen







>
>-S.
>>Uri



This page took 0.01 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.