From: jhc@m2lll.uucp (James H. Coombs)
Subject: Re: F-S II Game 8: analysis
Reply-To: jhc@iris.brown.edu.UUCP (James H. Coombs)
Organization: IRIS - Brown University
Date: Tue, 15 Sep 1992 08:21:57 GMT

In article <9209150332.AA01484@econ.berkeley.edu> jeff@econ.Berkeley.EDU (Jeffrey C. Ely) writes:
>In article 16355, jhc@m2111.uucp (James H. Coombs) writes:

>>>If only Deep Thought could see its way through the complications, then
>>>we need another word to describe missing the correct move in such 

>>Zarkov saw it, playing at about 2300 USCF.  I don't think it had to go
>that deep either. -Jim

>Ah yes, but that doesn't mean that Spassky blundered if we take blunder to 
>mean misanalyze the position far worse than a 2300 player would.  True,
>Zarkov has found the better continuation than Spassky found, but the
>question is did Zarkov assess its position as better.  Or put differently
>comparing the position resulting from 33. Qc3 and that arising from
>33. Rc6 does Zarkov *greatly* favor 33.Qc3?  My guess is that even after
>33. Qc3, Zarkov considered black slightly better as did CM 3000 (which
>I know, hawever, is weaker than Zarkov)

Well, Zarkov finds 33.Qc3 at blitz speed, which I estimate to be about
1800 USCF on my 486/25.

As for the scoring of the position.  After 33.Qc3, Zarkov gives
33...Nxc1 a score of -200 (where 100 is approximately the value of 1
pawn and negative scores are in Black's favor), and this score
persists: that is, there is no clear way for White to recover.  After
33.Rc6, Zarkov gives 33...Nxd2 a score of -550.  No question about it:
Zarkov finds 33.Qc3 significantly better than 33.Rc3 or any of the
other candidates that I have forced on it.

At blitz speed, Zarkov says -237 for 33.Qc3 and -527 for 33.Rc3.

What can I say?  ChessMaster is a toy.  Spassky was tired, not feeling
well, etc.  Fischer is manic; rusty, but boiling over still with
energy.  Dump CM and get Zarkov.

What does Zarkov recommend instead of 31.Rc1?  Well, at blitz, 31.Bg2
would be roughly equal (+21).  At 40/120, 31.b4 would be roughly equal
(+23).

>	The critical test is whether Zarkov preferred the position following
>33. Qc3 to its preferred move on mve 31.  Did Zarkov favor 31. Rc1?  I bet
>that even if it saw 31. Rc1 with the continuation 33. Qc3, it would have
>rejected Rc1 and never reached a position in which 33. Qc3 was a 
>possibility.

I don't understand this.  But, I still have the analysis up, and Zarkov
suggests, 31.b4 Na4 32.Rc1 Rxc1 33.Qxc1 Nb6, etc.  Of course, as you
play through, the evaluation changes.  That is, once we actually get to
move 33 in this sequence, it may find something much better than Qxc1.

>	So I guess what im saying is that we need to ask if 31. Rc1 is 
>strictly speaking a blunder.  From the point of view of an entity with
>a short horizon of foresight such as me, Zarkov, and presumably Spassky
>it appears to be so, but to Deep Thought II it is a brilliancy.  Here's 
>where perhaps we need a new terminology.

Well, we have yet to see any proof that DT II sees anything of
consequence.  At least *I* have seen only the statement that White has
all of the "winning chances."  I certainly don't see these chances.
Zarkov does not see them.  Although after 33.Qc3 etc., White does have
a passed pawn (but is still down the exchange).  As far as I'm
concerned, if White has "all of the winning chances," then Zarkov
should be able to see them.  If a 2300 program can't see them, then
they are not "all of the winning chances."  Or let's see some of those
variations!  (And why should we put a lot of faith into DTG
II---research code, remember?)

Now as far as "blunder" is concerned.  One can blunder into good luck
as well as into bad luck.  If Spassky did not see it, then it was a
blunder whether he found the right continuation or not.  Clearly, he
did not see it, and that was why he threw up his hands after tossing
out a couple of desparate moves.  It does not make much difference at
Spassky's level, but we neophytes need to be careful about
distinguishing luck from skill.

Finally!  As for "to Deep Thought II it is a brilliancy."  Nothing is
"to Deep Thought II."  DTII is nothing more than software being
executed on hardware.  It lacks attitudinal capacity.

--Jim