Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Interesting result from SSDF

Author: Amir Ban

Date: 01:03:07 06/10/00

Go up one level in this thread


On June 09, 2000 at 23:17:44, Robert Hyatt wrote:

>On June 09, 2000 at 15:18:01, Amir Ban wrote:
>
>>On June 09, 2000 at 10:33:33, Robert Hyatt wrote:
>>
>>>On June 09, 2000 at 06:26:17, Amir Ban wrote:
>>>
>>>>On June 08, 2000 at 16:10:16, blass uri wrote:
>>>>
>>>>>On June 08, 2000 at 15:25:22, Amir Ban wrote:
>>>>>
>>>>>>Ok, here's my two cents:
>>>>>>
>>>>>>The most likely estimate for the game outcome is the overall match result
>>>>>>(33.5/41). The probability for any *particular* sequence of 10 games (say the
>>>>>>last 10) to be 10-0 is (33.5/41)^10 = 13.3%.
>>>>>>
>>>>>>If you want probability for any sequence anywhere, the probability is larger, as
>>>>>>you point out.
>>>>>>
>>>>>>If you suspect the 10-0 result, you can argue that the most likely estimate
>>>>>>should discount this result, so this gives you a probability of (23.5/31)^10 =
>>>>>>6.3%.
>>>>>
>>>>>If you use the most likely estimate
>>>>>The probability for 10:0 is smaller than (23.5/31)^10 because there are draws.
>>>>>
>>>>>The result was +20, =7.-4 so if you use the most likely estimate you get
>>>>>probability (20/31) for Junior to win
>>>>>7/31 for a draw and 4/31 for a loss
>>>>>
>>>>>(20/31)^10=0.012493... so the probability is less than 2%
>>>>>
>>>>>I ignored the fact that the white probability is different from the black
>>>>>probability but not ignoring it does not change much the result because you get:
>>>>>
>>>>>(10/15)^5*(10/16)^5 that is 0.012558...
>>>>>
>>>>>If you do not ignore the last 10 games and ignore the colours you get
>>>>>(30/41)^10=0.043992...
>>>>>
>>>>>Uri
>>>>
>>>>All right, you are right about the draws.
>>>>
>>>>My presentation of the problem was more complicated than necessary. Here is the
>>>>question in its simplest form:
>>>>
>>>>A match of 41 games concluded with 30 wins, 7 draws and 4 losses. It is unknown
>>>>in which order these wins/draws/losses occurred.
>>>>
>>>>Out of all possible permutations with the same result, what percent of the
>>>>permutations have a sequence of at least 10 wins ?
>>>>
>>>>This is clear cut question for the combinatorics gurus in this newsgroup.
>>>>
>>>>There seems to be gross difference of opinion about the result of this, so until
>>>>we get an answer, we can have an opinion poll about the result.
>>>>
>>>>My guess: 40%.
>>>>
>>>>Amir
>>>
>>>
>>>As I mentioned before, I am simply worried that reusing the engine over and
>>>over might be the problem.  IE if you just crank up two copies of crafty and
>>>let 'em play, over and over, if one breaks, it will remain broken and will
>>>likely lose every game (or nearly every game) from that point forward.
>>>
>>>Since I don't test like this, it is very possible...
>>>
>>>And that would explain a sudden string of 0's at the end...  and it would
>>>explain things if the 0's stop after a restart or another tester plays games,
>>>since he would start a new crafty.
>>
>>Of course, that is a possible explanation for this otherwise incredible result.
>>
>>Another possible explanation is that there is a bug in Junior that something
>>doesn't reset correctly and the engine starts playing stronger than intended,
>>and wins every game. I definitely need to look into that.
>>
>>Amir
>
>
>Perhaps while you are looking, you can look into losing the sarcasm?
>
>eh?
>
>I don't ever recall you going 10-0 vs crafty on ICC.

It's not easy to do this while being censored. Not to mention being noplayed
after 4 consecutive games.

Amir


> So _something_ is
>definitely "up".



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.