Author: Gerrit Reubold
Date: 14:16:33 09/27/02
Go up one level in this thread
On September 27, 2002 at 17:03:35, Uri Blass wrote: >On September 27, 2002 at 16:25:54, Gerrit Reubold wrote: > >>On September 27, 2002 at 16:14:08, Uri Blass wrote: >> >>>On September 27, 2002 at 15:47:15, Peter Berger wrote: >>> >>>>On September 27, 2002 at 15:27:35, Uri Blass wrote: >>>> >>>>>On September 27, 2002 at 15:18:52, Peter Berger wrote: >>>>> >>>>>>On September 27, 2002 at 15:11:12, Uri Blass wrote: >>>>>> >>>>>>>On September 27, 2002 at 14:58:25, Peter Berger wrote: >>>>>>> >>>>>>>>On September 27, 2002 at 14:33:22, Uri Blass wrote: >>>>>>>> >>>>>>>>>Correction: >>>>>>>>>I meant one and only one of us is right if incredible luck happened. >>>>>>>>>of course in most cases we will discover that both of us wrong. >>>>>>>>> >>>>>>>>>Uri >>>>>>>> >>>>>>>>Read http://www.talkchess.com/forums/1/message.html?254769 . I am your friend on >>>>>>>>g5 :). >>>>>>>> >>>>>>>>Peter >>>>>>> >>>>>>>I read it and replied it without the friend. >>>>>>>simulation prove that out of 64000 games >>>>>>>only 2000 are practically played and >>>>>>>I win 1000 out of 2000 by not switching. >>>>>>> >>>>>>>With the friend I get the same and I see no reason to prefer a1 and not g5 if I >>>>>>>know that the host does not choose g5. >>>>>>> >>>>>>>If the host choose random squares the game is >>>>>>>practically the same because all the squares are the same >>>>>>>from the host point of view when he knows nothing about them. >>>>>>> >>>>>>>Uri >>>>>> >>>>>>The right assumption IMHO is not that the friend sits on g5 but that the friend >>>>>>always sits on the other field left the host didn't expose. >>>>>> >>>>>>Peter >>>>> >>>>>We assume that the host does not know the right square. >>>>> >>>>>suppose that the host strategy is not to expose a random square. >>>>> >>>>>62/64 of the games are canceled because the host exposed >>>>>the king >>>>> >>>>>Let look only in 64000 game that the host did not expose g5 >>>>> >>>>>62000 of them are canceled >>>>>I win 1000 of them and the friend win 1000 of them. >>>>> >>>>>The same is for 64000 games when the host did not expose g4. >>>>> >>>>>For every square that the host does not expose I have the same number >>>>>of wins and losses. >>>>> >>>>>Uri >>>> >>>>One last trial - to keep the analogy with the original Monty problem and the >>>>adding of additional doors. >>>> >>>>I think it is just like this: >>>> >>>>1.) You have the first choice -> you take a1 >>>>2.) The host starts opening doors, he opens 62 of them and none has the king (he >>>>is just lucky or he knows, doesn't matter). >>> >>>It is important. >>> >>>>3.) Then he adresses me : Which of the 64 fields that don't have Uri on them do >>>>you want to choose -> I choose the one not exposed yet >>>>4.) Then he adresses you: do you want to keep with your square or change to >>>>Peter's? >>>> >>>>There are only two interesting squares left - one of them has the king. But I >>>>think you will agree that yours sucks compaired to mine. >>>> >>>>Peter >>> >>>If the king was not exposed by luck then I do not agree. >>> >>>Last try to explain: >>>Let suppose he does not know where is the king. >>> >>>Let suppose that I am not allowed to change my choice and I win only if I chose >>>the king. >>>My chances are 1/64 to be right. >> >>Agreed. >> >>> >>>1)Do you agree that if he expose the king when he expose 62 squares then it is >>>bad luck for me and I lost the game? >> >>No. The game is canceled in this case. We assume the king is not exposed. > >I was talking about a new game and not about the old game. > >The rules in the new game game is that I win if the king is in a1 and I lose if >the king is in another square. > >I will try to explain more clearly(I will not talk about winning the game but >about your probability to be right in guessing) > >1)P(a1 is the real place of the king)=1/64 in the beginning of the game. Agreed. > >2)p(a1 is the real place of the king) is reduced to 0 if the king is exposed in >another square. Agreed, but that doesn't matter, because in the game which I discuss the king is _not_ exposed. > >3)p(a1 is the real place of the king) is increased if the king is not exposed >because it is not logical to assume that exposing squares can reduce the >probability of the king to be in a1 and cannot increase the probability of the >king to be in a1. No, looking at squares do not change the probability of the king being in a1, neither increase nor decrease. > >It means that the probability that you are right to assume that the king is not >in a1 is more than 1/64 if you know that the king is not exposed. > >Uri Greetings, Gerrit
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.