Opening Reports on the New Year's Database

Using the New Year's Database of Jerome Gambit (1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+), Blackburne Shilling Jerome Gambit (1.e4 e5 2.Nf3 Nc6 3.Bc4 Nd4 4.Bxf7+), and Semi-Italian Jerome Gambit (1.e4 e5 2.Nf3 Nc6 3.Bc4 h6 4.0-0/4.Nc3/4.d3 Bc5 5.Bxf7+) games, I enlisted ChessBase8 to run a series of Opening Reports. The results were enlightening.

Starting with 1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+, the Report found 6,507 games. White "scored badly" at 44%, while Black scored 56%.

As for Black's replies, 4...Kxf7 was played in 6,124 games, when Black "scored well" with 56%, as compared to scoring "averagely" (46%) with 4...Kf8 and "badly" with 4...Ke7 (30%).

These statistics, like all statistics, should be taken with a grain of salt. Still, it is clear at this point that Black gains nothing (and White loses nothing) by avoiding the capture of the Bishop. Too, if the Opening Report considers 46% to be "average", White's 44% is not far off the mark.

Finally, the Critical Line is given as 1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7 5.Nxe5 Nxe5 6.d4 Bxd4 7.Qxd4 Qe7 where White scores 33%. This is interesting, but Readers know that 6...Qh4+ is the actual critical line, even if it has scored poorly in the database.

I re-ran the Opening Report after 1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7 and was not surprised to find that while 5.Nxe5+ was played in 2,677 games and scored "averagely" with 53%, all other White choices scored "below average" (5.c3 47%;), "badly" (5.b3 43%; 5.d4 40%; 5.0-0 36%;) or "miserably" (5.Qe2 33%; 5.d3 32%; 5.a3 31%; 5.h4 31%; 5.Nc3 27%; 5.c4 25%; 5.Ng5 23%; 5.g3 0%; 5.Ng1 0%) – with the exception of 5.b4, transposing to the Jerome Evans Gambit, where White scored "well" at 67% (in 6 games).

I re-ran the Opening Report on 1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7 5.Nxe5+, and noticed that White scored 74% against 5...Ke8; 67% against 5...Ke7; 53% against 5...Nxe5; 45% against 5...Kf8; and 38% against 5...Ke6.

Clearly that last move needs more analysis on behalf of White. 

In general, it still looks like White does best to stick with the Jerome Gambit "book" and that Black takes more risks when he knowingly or unknowingly plays away from "book".

graphic by Jeff Bucchino, the Wizard of Draws

Stats (Huh?)

Readers might come away from examining the Jerome Gambit (1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+) database statistics – see "Stats (1)", "Stats (2)" and "Stats (3)" – with a small sense of confusion, as the Opening Reports seem to both show that White scores "better than average" in a number of lines; yet there are Critical Lines where White scores poorly.

(Readers might also want to compare the analysis with the "A Closer Look" series, which took a look at the Ninja Knights T3 Jerome Gambit thematic tournament: 1, 2, 3, 4, 5 ; as well as look at the Comments following "Jerome Gambit: Transylvanian Terror!")

This result reflects both the nature of sampling bias (that is, because of how the games were collected – that Jerome Gambit wins are more likely to be published and available to the researcher than Jerome Gambit losses – there are more opening successes than failures, despite the opening's "objective" strength); and the nature of the opening itself (defenders are often taken by surprise, become intimidated, and do not take advantage of the winning opportunities that are presented to them).

A comparable case would be a database that collected all available games in which Queen-odds were given. Although being a Queen up is usually considered enough of an advantage for all but the rankest of amateurs to win with (see Geoff Chandler's "Blunder Table"), it is highly likely that the results of the database would highly favor the odds-giver.

Stats (3)

Taking yet a further look (see "Stats (1)" for a preliminary peek and "Stats (2)" for a deeper one) at a ChessBase Opening Report from my Jerome Gambit (1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+) database requires simply continuing to advancing along the move order.

Thus: 1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7 5.Nxe5+ Nxe5 6.Qh5+ will dig deeper.

According to the Opening Report, White scores "above average" (59%), with 276 wins (57%), 18 draws (4%) and 192 losses (40%). White wins are "shorter than average" (37 moves), Black's wins are "shorter than average" (33 moves) and draws are "short" (30 moves).

Looking at Moves and Plans for Black, 6...Ke6 appeared in 229 games, where Black scored "below average" (38%). Recommended for White is 7.f4, while in the Critical Line White scored only 36%: 7...d6 8.fxe5 dxe5 9.Qh3+ Ke7 10.Qg3.

In 117 games Black played the alternative, 6...Ng6, scoring "below average" (41%). Recommended for White is 7.Qxc5. The Critical Line is then 7...Nf6, against which White has scored only 29%.

In 78 games Black played 6...g6, scoring "below average" (38%). Recommended for White is 7.Qxe5, although in the Critical Line 7...d6 8.Qxh8 Qh4 9.0-0 Nf6 10.c3 White has scored 0%.

An important 6th move alternative for Black, played in 53 games, is 6...Kf8, which scored well (63%). Recommended for White is 7.Qxe5, although the Critical Line, again, is daunting for the first player, as after 7...Qe7 8.Qf4+ White scored 19%.

Finally, Black infrequently played 6...Kf6 (3 games) and scored "miserably" (0%) after White's recommended 7.Qf5+.

Stats (2)

Taking a further look (see "Stats (1)" for a preliminary peek) at a ChessBase Opening Report from my Jerome Gambit (1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+) database is as simple as advancing along the move order a bit, and then asking the software to analyze.

So, a look at 1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7 5.Nxe5+ will dig deeper.

There are 856 games in my database with that line of play. The Opening Report says that White scores "well" with 69%: 510 wins (68%), 21 draws (3%) and 224 losses (30%). In addtion, White's wins are of "average" length (38 moves); Black's wins are "shorter than average" (33 moves); and draws are "short" (29 moves).

Looking at Moves and Plans, 5...Nxe5 was seen in 711 games, where Black scored "badly" 31%. The Opening Report recommends 6.Qh5+ for White, and gives as the Critical Line: 6...Kf8 7.Qxe5 Qe7 8.Qf4+ where White only scored 19%.

A fifth move alternative for Black, 5...Kf8, was seen in 18 games, and Black scored "well" at 56%. The recommended move for White is 6.0-0.

Also possible for Black was 5...Ke8, seen in 8 games, although he scored "miserably" with 0%; 5...Ke7, seen in 2 games, with likewise "miserable" results (0%).

Stats (1)

For what it's worth, let's look at some numbers, based on my Jerome Gambit (1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+) database.

Please keep in mind the caveats about this that I mentioned in my reply to Pete Bank's ("blackburne") Comment to "Fool me once..."

I use ChessBase 8 to store most of my Jerome Gambit games and findings.

If I look at the series of moves 1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+, and run an Opening Report, I can see that ChessBase finds 1,436 relevant games. About these, it notes that White scores above average – 57%; that is, White wins 693 (55%), Draws 32 (3%), and Black wins 528 (42%). Not surprisingly, it points out that the Drawing number is quite low, with 1/3 of those drawn games having fewer than 20 moves.

In addition, White's wins are "shorter than average" (35 moves), Black's wins are "short" (29 moves), and the Draws are "shorter than average" (34 moves).

Looking at Moves and Plans, I can see that 1217 games featured 4...Kxf7, with which Black scored "averagely" – 44%. The Opening Report recommends 5.Nxe5+ for White, noting that 5...Nxe5 6.Qh5+ Ke6 7.f4 d6 then occured in 97 games; 5...Nxe5 6.Qh5+ Ng6 occurred in 118 games; and 5...Nxe5 6.d4 Qh5 7.0-0 Nf6 8.dxc5 Qxe4 9.Nc3 Qb4 10.Nd5 occurred in 118 games. That last line is highly skewed: all 118 games were from a match between Deep Shredder 10 and Rybka 2.3.1.

Interestingly enough, the "Critical line" for White, in which he scored only 29%, is 5.Nxe5+ Kf8 6.Nxc6 dxc6, which certainly bears some looking into.

Althought taking the sacrificed Bishop seems the thing to do, the Opening Report shows that in 19 games Black played 4...Kf8 instead, scoring "below average" at 37%. The recommended response for White is 5.d3.

In 5 games Black responded with 4...Ke7, when he "scored miserably" with 20%. White's response should be 5.Bh5.