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Subject: Re: The need to unmake move

Author: Robert Hyatt

Date: 10:59:40 09/03/03

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On September 03, 2003 at 13:51:34, Gian-Carlo Pascutto wrote:

>On September 03, 2003 at 13:48:21, Robert Hyatt wrote:
>
>>Mine is tunable.  I run about 100 positions and pick the minply value that
>>optimizes all 100 the best.  I just checked and I am using 3 at the moment.  I
>>have not tested this recently.  I think 3 was the optimal value for my quad >700.
>>
>>I will probably test this again on my dual to be sure that I have already done
>>this correctly.
>
>You ignored my point, which is that saying that if you'll just split at 4 ply
>to alleviate that problem causes another problem.
>
>It's not 'free'
>
>--
>GCP

I never said _anything_ is "free".  However "optimal" != "free" in this
case.  And since I have no choice, I go for optimal, whatever that is.  There
is a cost for splitting.  If that cost is high, you have to limit the number of
splits.  Also, for obvious reasons, move ordering near the root is _far_ better
than move ordering near the tips.  Splitting where ordering is better is
always a good idea.

Note that I don't "just split at 4 ply" I split when there are >= N plies
remaining in the search, where N can be set.  I use 3 for the moment.  I have
run with 4 and 2 as well in the past, but for my program, my hardware, 3 was
best last time I tested.

I have noted that hardware influences this.  On my P6/200 quad box, N=2 was
better.





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