Games under 40 moves:

40%/34%/26%

Games over 40 moves:

38%/28%/34%

Under 40 moves:

36%/39%/24%

Over 40 moves:

37%/29%/29%

QUEEN'S INDIAN DEFENCE:

Games of 40 moves or less:
0.28 / 0.55 / 0.18

Games of more than 40 moves:
0.36 / 0.38 / 0.26

Interestingly, the huge proportion of draws in shorter games also now eats into white's scoring rate, but the advantage over black is significant. Black fails to equalize in longer games.

NIMZO INDIAN DEFENCE:

Games of 40 moves or less:
0.29 / 0.46 / 0.25

Games of more than 40 moves:
0.35 / 0.36 / 0.29

Similar statistics to the QID, though with greater success for black early in the game. Black does not quite equalize in longer games, and again draws are very common in shorter games.

DUTCH DEFENCE:

Games of 40 moves or less:
0.42 / 0.32 / 0.26

Games of more than 40 moves:
0.42 / 0.31 / 0.27

Not good for black at all!

MODERN BENONI (incl. Benko):

Games of 40 moves or less:
0.42 / 0.28 / 0.30

Games of more than 40 moves:
0.41 / 0.29 / 0.30

<Can you separate out Slavs from QGs? It would be interesting if the statistics bore out the modern preference for the Queen's Indian and Slav over the QGD, King's Indian and Gruenfeld.>

Under 40 moves:

40%/31%/29%

Over 40 moves:

38%/29%/33%

Similar results to Alekhine's Defense, though Black does better in short games and slightly worse in long ones. In fact Black's winning percentage in short games with the Pirc/Robatsch is as good as it is with the Sicilian, which surprises me. Of course, White's winning percentage is better than against the Sicilian.

One more interesting wrinkle: 54% of the games are 40 moves or less in the French and Pirc/Robatch. In Alekhine's Defense, 57% are 40 moves or less, which is bad news for Black. <whatthefat>, did you calculate that ratio for the Sicilian and Caro-Kann?

Although the French has the worst results overall of the three defenses, it is more popular than the Pirc/Robatsch and Alekhine's put together:

12,940/7,157/1,854

Percentage of games that are 40 moves or less:

1.e4
Sicilian: 56%
Caro-Kann: 55%

TARRASCH
Games of 40 moves or less:
From 1995: 0.32 / 0.46 / 0.22
From 1980: 0.31 / 0.49 / 0.20

Games of more than 40 moves
From 1995: 0.47 / 0.37 / 0.16
From 1980: 0.46 / 0.36 / 0.18

Black suffers badly in a longer game.

ORTHODOX
Games of 40 moves or less:
From 1995: 0.35 / 0.51 / 0.15
From 1980: 0.29 / 0.59 / 0.12

Games of more than 40 moves
From 1995: 0.44 / 0.33 / 0.23
From 1980: 0.41 / 0.39 / 0.20

Black's chances early in the game are very low, and he doesn't come close to equalizing in a longer game. Interestingly the drawing percentage has come down in recent times.

SLAV
Games of 40 moves or less:
From 1995: 0.33 / 0.49 / 0.18
From 1980: 0.31 / 0.52 / 0.17

Games of more than 40 moves
From 1995: 0.39 / 0.36 / 0.25
From 1980: 0.39 / 0.36 / 0.25

SEMI-SLAV
Games of 40 moves or less:
From 1995: 0.35 / 0.44 / 0.21
From 1980: 0.34 / 0.45 / 0.21

Games of more than 40 moves
From 1995: 0.37 / 0.36 / 0.27
From 1980: 0.37 / 0.37 / 0.27

OK, the Ruy Lopez. I wonder if the search (c60-c99) was comprehensive, since overall the Ruy Lopez is less common in the database than the French, which I find really hard to believe.

Under 40 moves:

32%/50%/18%

Over 40 moves:

39%/35%/26%

The "profile" of the Ruy is similar to that of a 1. d4 opening: relatively drawish in shorter games, but with a large advantage for White at any length. The <Spanish Torture> earns its name.

One of my pet opening theories was that, by making it harder to reach "classical" Spanish positions, the Marshall had significantly weakened the Ruy as a winning weapon. The statistics provide no support for my theory. The percentages since 1995 are exactly the same as the percentages since 1980, although (I think, anyway) anti-Marshalls have become much more common in the last decade.

Under 40 moves:

35%/46%/20%

Over 40 moves:

39%/42%/19%

Compared to the regular Ruy, Black does better in short games, and worse in long ones. Makes sense, given the Open Ruy's characteristics: better piece play, looser pawns. In any event, my personal score against Dr. Palmer's O/R is a solid 0.

Under 40 moves:

31%/55%/14%

Over 40 moves:

43%/36%/21%

To my surprise, terrible for Black! Slightly more drawish than the Ruy in shorter games, but the draws come at Black's expense, not White's; and thoroughly bad for Black in long games.

This undermines another one of my theories, which is that the Petrov combined with the Marshall had significantly reduced the value of 1. e4 as a weapon. Instead, the statistics indicate that the real problem with 1. e4 is the Sicilian, which scores better than any other mainstream defense (defenses to 1. d4 included).

Of course, there is the possibility that a given opening has the potential to equalize with black, but that it's statistics are harmed by it being practically difficult to play. Also, as you raised earlier, the average ratings of both colours would be a useful addition.

<Pleasure looking at this with you, <whatthefat>!>

Indeed!

<A bonus is that our little survey has validated my own opening preferences (1. e4 as White; Alekhine's Defense as Black). According to the database, my openings are to blame for my defeats, while I alone am responsible for my victories.>

Revised percentages for Alekhine's:

Games under 40 moves:

40%/34%/26% (same as before)

Games over 40 moves:

37%/30%/33%

Under 40 moves:

36%/39%/24% (same)

Over 40 moves:

39%/31%/30%

Under 40 moves:

40%/31%/29% (same)

Over 40 moves:

38%/30%/33%

Again, in longer games Alekhine's and the Pirc/Robatsch give similar, rather good results. But the Sicilian remains the champ at any distance.

53% and 59% are the correct ranges. The K.I.D. and Q.G.A. have relatively fewer games ending in 40 moves or less; Alekhine's has relatively more.

<It looks like 1. d4 games are a little shorter on average.>

Games of more than 40 moves
From 1995: 0.44 / 0.33 / 0.23
From 1980: 0.41 / 0.39 / 0.20 >

King's Gambit (C30-39)

40 or fewer:

45%/19%/36%

Not bad!

40 or more:

39%/31%/31%

White retains an advantage even in long games. Long ago, Bronstein pointed out (and demonstrated) that the King's Gambit often led to good endgames for White.

70% of King's Gambits last 40 moves or less. Clearly an opening for manly men (and women, like distinguished practitioner Judit Polgar). There are 1,325 King's Gambits in the database from 1995 or later.

Giuco Piano

40 or fewer:

38%/33%/29%

More than 40:

41%/26%/33%

Not as good for White as the Ruy, but better than I would have expected.

57% of Giuco Pianos last 40 moves or less. There are 1,887 examples in the database from 1995 on.

Two Knights

40 moves or fewer:

39%/28%/33%

More than 40 moves:

39%/30%/32%

One of the better results against 1. e4, and noticeably better for Black than the Giuco Piano. This is interesting since the Two Knights has a bad theoretical reputation right now. But openings select players, as well as the other way around; those who prefer 3...Nf6 are probably slightly more ambitious, more confident, better booked, and perhaps stronger on average than those who choose 3...Bc5.

57% of Two Knights last 40 moves or fewer. There are 1,426 Two Knights in the database since 1995. The Two Knights and Giuco together are more than four times as popular as Alekhine's Defense.

Evans Gambit (which is a subset of the Giuco, of course)

40 moves or less:

36%/28%/36%

More than 40 moves:

29%/29%/42%

Not good for the Cinderella of openings! 57% of Evans Gambits last 40 moves or fewer. White's best hope seems to be that Black will skewer him in the middlegame, rather than slowly roasting him in the ending. In light of these results, it's not surprising that there are only 168 Evans since 1995 in the database.

Vienna Game

40 or fewer:

33%/35%/32%

More than 40:

36%/31%/33%

If White wants a quiet life with no pesky opening advantage, 2. Nc3 seems like an ideal choice. Surprisingly popular: There are 918 examples since 1995. Strange that White does slightly better in the Vienna in long games than in short ones.

Here's a bloodbath of mine in this DB playing Black from the humble beginning of 1.e4 e5 2.Nc3: http://chessgames.com/perl/chessgam...