Hi Robbie (The Scottish Championship)

Originally posted by greenpawn34
Hi Paul,

That must an OTB database. After 2.Nf3 is White playing the 4.b4 line.
or are some chickening out with 3.exd5.

1. e4 e6 2. Nf3 d5 3. e5 c5 4. b4

[fen]rnbqkbnr/pp3ppp/4p3/2ppP3/1P6/5N2/P1PP1PPP/RNBQKB1R b KQkq - 0 4[/fen]

On here after 4.b4 it's 55% wins v 34% losses from 220 games.
(on here if I get this far I have 100% - ).
...[text shortened]... ked a win.... infact when I
think about it, I am probably losing after 4.b4! in all the games.)

I think the top players all use your formula- especially Carlsen, who often does not seem to care about an advantage of the opening, and instead simply aims to play better chess and win in the end.

I am not good enough to offer a mathematical proof, but it seems to me that any variation, when played in a sufficient number of games, tend to favor white in the range of 54-56%.

When the percentage is above or below those numbers, the number of games is usually much smaller than normal, which implies that either white or black tend to avoid repeating the path.

A winning line only needs one crushing innovation to relegate it to the trash heap, which ends the use of the variation but preserves its (very misleading) winning percentage, as no new games are played to change it.

One time I was at a class with GM Lars Bo Hansen, and he mentioned that he pays almost no attention at all to the win/loss percentages for openings, because there are so many ways that a game can be lost that are irrelevant to the opening. He was talking about OTB play mainly, but it has influenced my thinking and playing here on the site in the last year or so.

HI Paul,

Lars Bo Hansen, is right the %'s never look at the length of the game - just the result.
So you have refine the search to say 25 moves and that may give a better indication
of how critical an opening variation is, especially a tactical sac opening.

Also stats pick up the weaker players playing an uncommon opening
to get the stronger players out of main line theory thus giving the uncommon
opening a really bad reputation.

For example the Morra Gambit is viewed with great suspicion at the top level
but here the standard is lower and the %'s look OK for the Morra.

The Latvian Gambit also suffers from this (which is good for me.)
If on an large OTB database it usually scores low then if you look at
the grades you can figure that Black was probably going to lose
no matter opening they played.

However if you do an individual search of just your games or another players
games the stats may spot something you were unaware off.

Hi GP,

I have not considered the idea of restricting the search by number of moves to get a truer idea of results. I am going to try that!

I have used searches of 20 to 25 moves in particular openings when I start to learn them, just to get an idea of common tactics in the opening.

When I first started playing the French, I struggled with what to play against the Exchange Variation, so I made a special database of French Exchange games that ended in 20 moves or less.

I then went through with a computer to eliminate the quick draws, What was left was a bunch of games where a tactical shot ended the game suddenly.

Not only did I learn a bunch of tactical patterns directly related to what I was going to play, I also learned a newer, more relevant (for me) respect and appreciation for the play surrounding having an isolated pawn.

For those who are not sure what I mean, I offer this gem:

{EDIT} I recommend inverting the board before playing through it!

Hi Paul

I remember that game, Tatai - Korchnoi it was published in a mags and newspaper
columns. It started me off on a surge of playing the Exchange French as White
with c4 to see if I could get a Korchnoi type position a tempo up.

That's something I've done with most Black opening traps. Can I spring it from the
White side dropping a tempo to lure them in. Hence 1.e4 Nf6 2.f3 e5 3.f4!

But the year in your posted header is wrong. It was 1978 when I chess daft.

There are some wonderful finishes in that game. Pity White resigned.

Originally posted by greenpawn34
Hi Paul

I remember that game, Tatai - Korchnoi it was published in a mags and newspaper
columns. It started me off on a surge of playing the Exchange French as White
with c4 to see if I could get a Korchnoi type position a tempo up.

That's something I've done with most Black opening traps. Can I spring it from the
White side dropping a tempo ...[text shortened]... P1/R1B2RK1 w - - 0 15"]
15. Qd1 Nxf5 16. Nf3 Bxf2+ 17. Kh1 Ng4 18. Qxe2 Qh2+ 19. Nxh2 Ng3[/pgn]

The header has 1978 as when the game was played. The "1999" reference was when it was added to the database, I believe. Not sure about that, though.

Ha! I see it now, I only saw the 1999.