Computer Chess Club Archives


Search

Terms

Messages

Subject: ECM errata (801 - end)

Author: Amir Ban

Date: 08:31:02 03/09/98



This is the last installment in the ECM errata report. I've been busy
with other matters recently, so this took some time. I did not review
yet Howard's and Bruce's comments to the latest batch, but, on
experience, they are reliable.

I hope now Don and others can take on this and compile the ECM98 suite.


No. 810 (Rxg6+):

Is the intent here: 1.Rxg6+ hxg6 2.Nxg6 fxg6 3.Qc2 ? If so 3...Ne5
4.dxe5 Ne4.

Recommend: Drop it.


No. 818 (Rxg6+):

Rxg6+ evaluates to around +4. I find e4, threatening Rxg6+. I evaluate
it higher at +5.6.

Recommend: Add e4.


No. 824 (Nxf3):

Rxf3 also works, and evaluates about the same (+2.8).

Recommend: Add Rxf3.


No. 827 (Rxf3):

I find 1...Rxf3 2.gxf3 Qh4 3.Re1 and white's mate threat makes this line
doubtful. Junior prefers a quiet Qh4.

Recommend: Investigate.


No. 833 (Nf6+):

I can't find a convincing line after Nf6+ gxf6, but the quiet Qg3 seems
to win (+122).

Recommend: Drop it.


No. 841 (Nxe6):

I find this line 1.Nxe6 Qxe6 2.Nd5 Kd8 3. Qd2 Qe5, which is not good
enough.

Recommend: Investigate.


No. 846 (Rxe3):

I'm not convinced: 1...Rxe3 2.fxe3 Nxe3 3.Qd2 Bxd4 4.Ndc5 is not worth
Black's trouble.

Recommend: Investigate.


No. 852 (Rxb2):

Nd3+ is even better (Rxd3 is forced. If Bxd3 Bxc3).

Recommend: Add Nd3+


No. 856 (Rf1):

Black needs to draw. It's probably right, but too deep for me. I see
1... Rxf1 2.Rxf1 Rxf1 3.Qe2 Bg1+ 3.Kh1 Rc1 but it's not over yet.

Recommend: Investigate.


No. 858 (Bxh2+):

Hard to make a ruling on this: 1...Bxh2+ 2.Kxh2 Qh4+ 3.Kg1 fxg2 4.Kxg2
Rxf2+ 5.Qxf2 Qg4+ black can probably get a perpetual here, but to prove
it is not easy.

Recommend: Investigate.


No. 860 (Qd8+):

This is bad. The assignment "white to draw" assumes that black is
winning, which is not the case. I find Qd3 +155. If 1...bxa4 2.Bxf7+!
wins.

Recommend: Drop it.


No. 864 (Nf5):

(Black to draw) This is probably bad: 1...Nf5 2.Qxd5 Ng3+ 3.Kh2 (I think
even Kg1 is good enough to win) Ng1+ 4. Kg1 Qh2+ 5.Kxf1 Qf4+ 6.Ke2 Qxc1
7.Qxf7+ black is lost.

Recommend: Drop it.


No. 865 (Nxg5):

Nxg5 draws, right, but who wants to draw here ? I get a plus score for
a5.

Recommend: Drop it.


No. 866 (Rg8+):

The idea is that Kh5 loses and Kh6 is a perpetual after Ne5, but what
about Kh4 ? I get this breathtaking line: 1...Kh4 2. Qe2 Bb5 3.f3 Bxd3
4.Qe1+ g3! 5.Rg4+ Qxg4 6.fxg4 Be4! and I count this as good for black.

Recommend: Drop it.


No. 867 (Rxh5):

Why does white want to draw here ?

Recommend: Drop it.


No. 875 (Qg1+):

Why does black want to draw ? I want to play 1...Bxc5 2.Rxc5 when 2...f5
or 2...Qf6 are to black's advantage. In any case, if black insists on a
draw, he can play 2...Qg1+ now, so this is at least a cook.

Recommend: Drop it.


No. 879 (Rd2):

This is unclear. First, Rd2 does draw (2. Qxd2 Nxf2+ 3.Kg1 Nxe4, or
2.Qc3 Rxb2 etc.), but then so does Nxf2+ by transposition. Second, I
play Nxf2+ with intent of maintaining a black advantage, though this may
be wrong. My line is: 1...Nxf2+ Kg1 2.Nd3 Bxd3 3.Qxd3 Qg6+ 4.Kf2 Qg2+
5.Ke3 Qxb2 unclear.

Recommend: Drop it.


Amir



This page took 0 seconds to execute

Last modified: Thu, 15 Apr 21 08:11:13 -0700

Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.