A Closer Look at the Big Picture (Part 1)

Responding to Jerome Gambit Gemeinde member Pete Banks' (blackburne) request for statistics (see his comment on "Another Closer Look") I consulted the updated New Year's Database for answers.

At the moment, the database contains 7, 298 games that begin 1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+.

As expected, the vast majority of the games have the Accepted response of 4...Kxf7. For those games, White scores 44%. 

Only 192 games – 2.6%, – illustrate the Jerome Gambit Declined. For the record, White scores a surprisingly low 55% against 4...Kf8 and a more robust 72% against 4...Ke7.

Of the 7,298 Jerome Gambit games in the database, 3017 (42.5% of the Jerome Gambit Accepted games ) feature the classical 5.Nxe5+, with which White scores 53%.

A tentative conclusion, then, is that classical lines (i.e. those going 1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7 5.Nxe5+) score better than the average for all Jerome Gambit games in the database.

At first glance, this may be surprising, as computer evaluations give most of the "modern" variations higher ratings than the classical ones. However, what may be at work is is experience and familiarity – it may turn out that those who play the classical variations are more likely to be "old hands" in playing the lines, and this provides them with a competitive edge.

The question for Black at this point is: should he take White's Knight? The statistics suggest that Black should. The alternatives: 5...Kf8 is seen in 100 games, where White scores 49%; 5...Ke8 is seen in 49 games, where White scores 60%; 5...Ke6 is seen in 18 games, where White scores 61%; and 5...Ke7 is seen in 8 games, where White scores 63%.

Those defending against the Jerome Gambit might want to look at that 5...Kf8 line, both as a surprise weapon and as the one non-main-line choice that decreases White's winning percentage in the classical Jerome Gambit Accepted from 53% to 49%.

Most of the classical Jerome Gambit Accepted lines (95.7%), then, begin with 1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7 5.Nxe5+ Nxe5. The results from the database are indifferent as to whether White follows up with either 6.Qh5+ (2,182 games) or 6.d4 (699 games) as the first scores 53% for White and the second scores 52%.

An indication of how the New Year's Database can skew reality, however, is that after 6.d4, arguably the strongest reply for Black is 6...Qh4, yet in the 160 games where that move order appears, White scores 77%.

We will look at how White does against the various main line defenses to the classical Jerome Gambit, tomorrow.