So you're saying that enabling lazy eval at PV nodes helps if you've done it right, and makes it clearer in test results if you haven't? That sounds like an unqualified win in the long term. Another reasonable approach, of course, is not to use lazy eval at all.
No I am not saying that.
I've said ...

I found it easy. Run enough games to measure Elo accurately, and then tune the value up and down to reach the max point... I didn't find "lots of local maxima" points. Just one. I don't see why there would be many. If you are too conservative, you don't get the speed gain and slowing down too much ...

You can't gain more than 2-3% of speed by applying lazy eval on PV nodes. An you can loose much more than 2-3 elo on that. Bad idea in general.

If you do it right , and it indeed does help in non-pv nodes, I see no reason why it would hurt along the PV (but maybe it is engine-specific).

Would ...

Elsewhere I read that Houdini improves upon ippo* in part by implementing lazy eval on pv nodes rather than just on cut and all. It doesn't seem that that would be very difficult to implement in Ivanhoe's pv_node.c.

Do other engines typically do lazy on pv nodes? Why would that or how could that ...

benstoker wrote:Anybody got a link to nice graphic that illustrates cut, all, pv, cutoffs, alpha,beta, fail high, etc.? Not equations, but boxes and lines and trees!

I like picture books!

Wikipedia is your friend .
http://upload.wikimedia.org/wikipedia/e ... nmaxab.gif

I was looking at Sentinel's Fire code, and null_move.h. It appears as though the null_new_depth function defined in null_move.h is not actually used. The code looks interesting and I was wondering if I am wrong and that the null move routines do indeed use this. Can you enlighten me?
It's an ...

It depends on computer. For example, my latest version of Strelka (based on the code of Rybka 3) show the following speed:

Core Duo E6750: 75% faster than Rybka 3
Core I7 920: only ~50% faster than Rybka 3

(both 32-bit and 1-cpu versions).
Is it possible that popcnt implementation in Rybka 3 is ...

orgfert wrote:At talkchess there is none.

You all (Bob included) just wave how Sam blows. He gives you a little illusion of control and power, but in the end it's his own interest that is supported. Whether his interest is classic commercial interest as CB is another question.

And let's not forget the disassembly posted here: http://open-chess.org/viewtopic.php?f=3&t=534 . Look, I don't care that Houdini is derived from Ippolit or Robbolito. I just care that Robert Houdart continues to insult my intelligence by lying about it, in the face of overwhelming evidence ...

Chris Whittington wrote:I have no idea who the anonymous stalker is

That one is easy, a frequent mod from CCC .