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Subject: Re: Hashing double bounds

Author: rasjid chan

Date: 04:13:12 06/21/05

Go up one level in this thread

On June 21, 2005 at 04:47:27, Vasik Rajlich wrote:

>On June 20, 2005 at 15:18:05, rasjid chan wrote:
>>I have implemented hashing 2 bounds after reading fruit does this.
>>It is fairly complicated to do and I just want to see if it is done wrongly.
>>I measured the figure
>>  hash-hit-return-by-2nd-bound/total-hash-hit
>>Per game move it is 0.000 almost all the time.
>>Ocasionally it has 0.001 and almost rarely 0.002.
>>If others have much higher figure then this,I suspect my double-bound is done
>>badly. It is difficult to debug except through usual hit statistic.
>>If this 2nd bound statistic is correct, then fail-soft propagation
>>of exactness is far better. For full-search FL exactness,it starts from 2/3%
>>and drops to about 1% for whole game.
>I don't understand this sentence.
>You'll have exactness when your scores are inside the windows.
>You'll also have exactness in some very rare cases very close to the horizon, as
>we discussed in the thread below. (This applies only to your custom algorithm.)

I now have statisic permanent (better) in my log output.
The figure mentioned above is just 1 game(that's me).

I measure only for full search fail-low and exact(w/o the algorithm,always
upper) and NOT exact when scores within windows;


I summed nominator and denominator cummulatively as game proceeds.
For the whole game, it may vary  from 2 - 6%.

This statistic I think is better then expected and significant.
Of course none can expect something like 10-15%.

If nullmove adds 150-200 ELO points as some say, then this (beefed-up fail soft)
may add 15-20 points and is free;

Best Regards

>Best regards,
>>Best Regards

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