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Subject: Re: About qsearch...

Author: Christophe Theron

Date: 08:44:06 12/30/01

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On December 30, 2001 at 11:14:19, Severi Salminen wrote:

>>The first use of SEE (historically) is not to sort capture moves.
>>The first use of SEE is to replace what we call now QSearch.
>
>Ok.
>
>>You arrive at a horizon node. Now you want an evaluation of this node. There are
>>two main ways of doing this:
>
>Ok, I didn't remember what horizon node means.
>
>>1) you call your SEE, and it tells you how much material the side to move can
>>win in this position (by doing a Static Evaluation of the possible Exchanges
>>from this position). You return a score of eval+SEE (or eval-SEE depending on
>>your conventions).
>>
>>2) you call the QSearch, which is going to try all the possible captures and
>>return a minimaxed score.
>>
>>
>>We are talking in this thread about the advantage of 1 on 2 (or vice-versa). So
>>we want to compare the difference of the tree size of 1 or 2.
>>
>>While I understand that you want to count horizon nodes in the QSearch (after
>>all each horizon node is the root of its QSearch), horizon nodes are also
>>visited by the first method (SEE).
>>
>>So in order to compute the difference in visited nodes of the two methods, you
>>need to count QSearch nodes that would not be visited by the SEE method. So you
>>don't count horizon nodes (you don't count the root of the QSearches, only the
>>moves or nodes which are generated BY the QSearch).
>
>And when you (or was it Ed) said you spend 15% of nodes in QS you exclude
>horizon nodes?



It was Ed, but yes I think he was excluding horizon nodes.




> I think my search will look a lot better with this new counting
>method :) If I count the way I used to do, I have 65% of all nodes are qnodes.
>I'll test what the number is if I include horizon nodes to actual nodes and not
>to qnodes.
>
>I think we should set some standards for these bloody nodes and qnodes...



Let's say that a qnode is a node GENERATED BY the QSearch.

A node is a node searched by the main search or the QSearch.

qnode_count / node_count <= 0.30 if your QSearch is working reasonably well.



    Christophe



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