Search found 250 matches

by MichelG
Tue Jun 23, 2026 08:11
Forum: Draughts, Computer, Internet
Topic: Internet engine matches
Replies: 504
Views: 507526

Re: Internet engine matches


What on earth is 'TT-size = 16'? That means it used a hash-table of 65 KB, does not seem very appropriate with 16 threads sharing the hash-table.

That version of the engine does not know 'Bucket-size', it should be 'Bucket-shift = 2', it clearly was in the ini-file when I sent you this engine ...
by MichelG
Sun Jun 21, 2026 22:07
Forum: Draughts, Computer, Internet
Topic: Perft
Replies: 276
Views: 327528

Re: Perft

I agree with Joost here. 2030 is way to pesimistic.

OpenAI intends to have a automated AI researcher in 2027. Surely it can write a simple draughts-program far before that.

In fact, i think you can do it right now.

What will change is that if you do it now, you may need several days of prompting ...
by MichelG
Sat Jun 20, 2026 11:35
Forum: Draughts, Computer, Internet
Topic: Perft
Replies: 276
Views: 327528

Re: Perft

I just asked openAI codex to optimise the speed. It thought and experimented for 10 minutes, and it increased speed by 11% for the move generator.

Here is the newest perft for dragon, on an intel i9-13900KF, running at 5.4 Ghz. Nps in milions/second.



bb bb bb bb bb
bb bb bb bb bb
bb bb bb bb ...
by MichelG
Thu Jun 18, 2026 07:29
Forum: Draughts, Computer, Internet
Topic: Dragon v4.7
Replies: 14
Views: 2291

Re: Dragon v4.7

> The program is recording the moves incorrectly during the game.
I will fix this next version

> I get the impression (I may be wrong) that the measurement is roughly the same as if I were using 16 threads.
16 or 32 threads will not matter that much. Depending on your processor, it is probably ...
by MichelG
Tue Jun 16, 2026 21:17
Forum: Draughts, Computer, Internet
Topic: Dragon v4.7
Replies: 14
Views: 2291

Re: Dragon v4.7

Hi Krzysztof,

I will have a look at the issues you have.

Note that dragon 4.7 is not stronger than the previous version. And you still can use the old databases.

Michel
by MichelG
Sun May 10, 2026 20:51
Forum: Draughts, Computer, Internet
Topic: Dragon v4.7
Replies: 14
Views: 2291

Dragon v4.7

It has been a while, but Dragon version 4.7.0 is now available:


New look, new icons
Removed all references to paid version/registration. It is all free now.
Solved crash if you used 32 or more processor cores (engine is unchanged otherwise)
You can now download the 6 piece endings from view ...
by MichelG
Sat Jan 13, 2018 17:52
Forum: Draughts, Computer, Internet
Topic: Breakthrough Draughts
Replies: 203
Views: 152562

Re: Breakthrough Draughts



Hi Michel,

I understand but I do not see clearly how the tempo_difference can be estimated by the patterns.
Let's take a simple example. Suppose you are dealing only with classical game. With a separate feature and by dividing the tempo_difference in for example 20 possible values from -10 to +9 ...
by MichelG
Fri Jan 12, 2018 20:32
Forum: Draughts, Computer, Internet
Topic: Breakthrough Draughts
Replies: 203
Views: 152562

Re: Breakthrough Draughts



Hi Michel,

It seems I have a different view (but I have not your experience in reinforcement learning !)

I agree with you that the tempo_difference can be estimated by the patterns alone but does that mean that we should avoid to use such fixed feature?
My view is the following : because the ...
by MichelG
Sun Jan 07, 2018 14:59
Forum: Draughts, Computer, Internet
Topic: Breakthrough Draughts
Replies: 203
Views: 152562

Re: Breakthrough Draughts



Hi Michel,

Concerning tempo difference do you also consider the patterns themselves can do the count or do you think that this feature is irrelevant?

I think the question is whether you can estimate the tempo difference by using patterns alone. The answer is a definite yes here. In fact, you ...
by MichelG
Wed Dec 27, 2017 20:15
Forum: Draughts, Computer, Internet
Topic: Breakthrough Draughts
Replies: 203
Views: 152562

Re: Breakthrough Draughts

Hi Michel,

I never tried that experiment, but it is not intuitive to me that it would only be a minor disadvantage. Without an eval term for man difference, I would expect the engine might toss a piece just to gain some minor positional advantage. Do you understand why this doesn't seem to be a ...
by MichelG
Fri Dec 22, 2017 09:41
Forum: Draughts, Computer, Internet
Topic: Index funtion for eval func
Replies: 6
Views: 10500

Re: Index funtion for eval func

Oh, I thought there were better index functions. Better = less memory :P

I am using this for checkers as well and initial resullts were quite promising. May I ask which optimization algorithm u use for the logistic regression ? I tried stochastic graidient descent which works but is still rather ...
by MichelG
Wed Dec 20, 2017 08:54
Forum: Draughts, Computer, Internet
Topic: Breakthrough Draughts
Replies: 203
Views: 152562

Re: Breakthrough Draughts



In order to solve the problem you mentionned I implemented two points:
1) I initialised the value of my 20 features to a value near from +2000
2) As soon as I want to modify a value I take into account a handwritten constraint saying that these values have to be ordered.

Concerning the fixed ...
by MichelG
Tue Dec 19, 2017 20:15
Forum: Draughts, Computer, Internet
Topic: Breakthrough Draughts
Replies: 203
Views: 152562

Re: Breakthrough Draughts



Hi Michel,

Maybe I am wrong but it appears to me that by calculating your f function you consider that the piece-difference is associated only one feature. Is it true?
FYI in my implementation each piece-difference value (from 1 to 20) is associated to one feature among 20. That way the learning ...
by MichelG
Tue Dec 19, 2017 18:39
Forum: Draughts, Computer, Internet
Topic: Breakthrough Draughts
Replies: 203
Views: 152562

Re: Breakthrough Draughts

I don't think there is any 'human' meaning to the function. It just maps -infinite to +infinite to the [0,1] range, and does so with some particular nice properties.

One thing to consider is that when for example you are 5 pieces ahead and say f=2.5, winning another piece doesn't increase the ...
by MichelG
Mon Dec 18, 2017 21:30
Forum: Draughts, Computer, Internet
Topic: Breakthrough Draughts
Replies: 203
Views: 152562

Re: Breakthrough Draughts

Hi Gérard,

The learning that i implemented, uses the logistic function to map the sum of features to a winning rate:

winrate = 1/(1+exp(-f))

The winrate is the number of points you can expect to gain from the position (loss=0, draw=0.5, win=1.0), f is the sum of the feature weights. The learner ...