Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: No but ...

Author: Rafael Andrist

Date: 08:38:51 01/11/03

Go up one level in this thread


On January 11, 2003 at 10:45:14, GuyHaworth wrote:

>I haven't studied the Nalimov code but if the 'subgame reverse-inheritance'
>phase is changed as follows:
>
>a)  side mated ==> DTC = DTM = 0
>b)  stm converts to win ==> DTC = 1 rather than DTM = dm+1
>c)  stm forced to convert to loss ==> DTC = 0 rather than DTM = dm
>
>then Eugene's code generates DTC EGTs rather than DTM EGTs.
>
>Maybe the EN-program-cognoscenti know where this coding is?

Changing the code would not be a problem, but it would be necessary to
_generate_ the EGTB again with DTC metric and this means re-generating already
existing information. A direct conversion would be much faster.

>This seems a safer route to creating the DTC EGTs.

If you do not trust the Thompson data, several cross-checks are possible after
conversion:

1) win(DTC) = win(DTM) etc. comparing illegal positions is not possible because
Thompson metric does not make a difference between draw/illegal.

2) DTM >= DTC

3) running the self-consistency check for EGTB

All this together would still be faster than re-generating the database.

regards
Rafael B. Andrist



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.