Crafty

[hyatt]

Isn't there some "floor" for Elo or do I mis-remember? Or can it actually go negative?

I REALLY wanted to have something like "Elo 2150" and it would play like a 2150 player. But that is REALLY hard given all the wildly varying hardware performance options around...

[Adam Hair]

Isn't there some "floor" for Elo or do I mis-remember? Or can it actually go negative?

Since Elo is a relative measure, it can be negative.

I REALLY wanted to have something like "Elo 2150" and it would play like a 2150 player. But that is REALLY hard given all the wildly varying hardware performance options around...

The best thing I can do is to calibrate my ratings to the SSDF ratings. They made an attempt to calibrated their ratings to human ratings. That at least would get the computed Elo values for the different Crafty skill levels in the ballpark with human ratings. Short of finding rated volunteers to play against Crafty, that is the best that can be done. And of course all of this would be relative to my computers and would vary an unknown amount on other hardware. Still, it would not be extremely inaccurate.

[kingliveson]

Since Elo is a relative measure, it can be negative.

Not sure I agree here, unless ... "negative probability"... well ...

[Adam Hair]

Since Elo is a relative measure, it can be negative.

Not sure I agree here, unless ... "negative probability"... well ...

White Score = 1/(1+10^(-Elo Diff/400)) where Elo Diff = difference in Elo between White and Black

If White was 3000 Elo and Black was 2950 Elo, then White's predicted score would be 57.15% .
If White's Elo was -50 and Black's was -100, the predicted score for White would be 57.15% .

Since only the difference in Elo values is used in the model, it does not matter what those values are.

[KilgoreTrout]

Besides your facts being incorrect about Crafty, Robert Hyatt is a pioneer of computer chess, so you should show some respect. He has been a major contributor. I have known of his name since the days of Cray Blitz, and not many other people have had such staying power in the field. Many others have come and gone.

Crafty is still a great program, with regular updates, and I enjoy it. Also, it's not like Dr Hyatt is charging anyone money for his engine! He is an academic, and publishes his ideas, instead of hiding them for commercial reasons. I have nothing against commerce, but it is different motivations when one seeks money vs advancing the field with openness.

THANK YOU DR HYATT. I have no doubt computer chess would not be where it is now without your contributions. That's true of others as well, of course, but most are not still active.

PS: Yes I am a new member here, but that does not change the facts. BTW, my first computer chess "experience" was playing Atari Video Chess, then Cyrus, then Sargon, and so on. All the old names, I have been around the block too, as an enthusiast, not a programmer (I'm an EE, but admit to being a mediocre coder, just never developed the patience. Those damned punch-cards were to blame, I bet. I was born just a few years too early!). Looking back, it's kind of amusing to see freeware Crafty being dissed. I wish I had anything even close back in the day. Hah, how spoiled we have become to complain of only semi-God-like chess engines But I digress......

[Prima]

Besides your facts being incorrect about Crafty, Robert Hyatt is a pioneer of computer chess, so you should show some respect. He has been a major contributor.

Crafty is still a great program, with regular updates, and I enjoy it. Also, it's not like Dr Hyatt is charging anyone money for his engine! He is an academic, and publishes his ideas, instead of hiding them for commercial reasons. I have nothing against commerce, but it is different motivations when one seeks money vs advancing the field with openness.

THANK YOU DR HYATT. I have no doubt computer chess would not be where it is now without your contributions.

I second that. And as you noted relative to those who came and went, are invariably those with commercial interests. The very same individuals who benefited from CCC forum & its previous and/or early forum inception, and as soon as they got the free ideas/codes/whatever for free, they then go commercial only to quit when there's no more free stuffs for them to grab and sell.

Gets even worse or funnier, depending on your views: In Rybka forum, it's always amusing to see supposedly manly men play the female harlot whore with their skirts worn-up high to their loins, with their high stiletto shoes, and lips painted crimson-red to any individual who produces more ELO from GPL/public codes - which they themselves previously deemed it was stolen from their beloved Rybka's codes - albeit factually unsubstantiated to date. And then "they" condemned it - only to turn around and buy/support the supposedly stolen Rybka codes. Go figure this Babylonian, twisted logic ubiquitous in that forum. Short-term memory and/or amnestic disorders comes to mind, in addition to their effeminate propensities. But don't expect that to deter them. For a few [unethical] +ELOs, they'll even bend-over shamelessly & unchallenged to "the man" to have his way and do his "thing" with them. But then again, that's the definition of a [female] whore.

Heck, I can imagine someone else coming along and does the same thing Robert Houdart did to Ippolit/RobboLito (Rybka?). The useless top-dog whores - proficient at running their mouths ignorantly BEFORE cognizance AND facts - will of course condemn the new improved engine that's now stronger than Houdini - just likke they condemned Houdini in favor of Rybka/Vasik Rajlich. Then when the new engine is substantially stronger; then watch their tunes change and their noses begin to turn brown and BROWNER in color - from them doing you know what. Then, just like they abandoned Vasik Rajlich for Houdini, they'll do the same to Robert Houdart - essentially wearing their infamous short-mini high skirts & stilettos & crimson red lip-paints for the "new man". Whoredom is effected once again. Ahh....the vicious cycle of amnestic disorders is commenced once again. Over an over...

Crafty is one of those program that is original.

BTW KilgoreTrout, welcome to the forum. It's peaceful & friendly here. As for me, I'm still taking an indefinite time off of chess.