Monday, May 11, 2009

Fifteen Minutes of Rook Endgame

Stop the press, rewrite the classics, cut out the cliches forever: because it turns out, not all rook endgames are drawn.

Not only that, but they're a great deal less drawish than many other endgames - at least according to Andrei Volokitin and Vladimir Grabinsky in Perfect Your Chess (page 38):
"All rook endings are drawn", according to a common piece of chess folklore. We decided to distrust emotion and check the figures, comparing the percentages of draws in different types of endings, using a database of more than three million games. The results were very surprising. Bishop endings turned out to be the most drawish, with 47%. Second place went to queen endings on 43%. Even more surprising was the third place for knight endings, at 40%. And the notorious rook endings came only second-last at 38%, with pawn endings naturally turning out to be the least drawish at 27%.
And what else can I tell you?

Unfortunately, not much. Volokitin and Grabinsky don't say what the database was. They don't say what criteria qualified a position as a rook endgame: only one rook each? two rooks each as well? what about one rook + pawns v two rooks? They don't say whether they factored out trivial cases, e.g., where one of the rooks is instantly lost, the player only playing on because of say the clock. And it seems a shame they didn't repeat their analysis for tablebase positions only, and then again for Grandmaster games only - assuming the database wasn't GM games only to begin with, that is.

So! Can any of our more-knowledgeable readers fill in the gaps? Or might any of our more tech-savvy readers like to research all this further, for instance by analyzing with their own data and tablebases?

If so - let us know what's what in the comments. Or indeed if you're able to put in a lot of work into answering these types of questions, you could even drop me a line and I'll see if I can make a whole future post out of it, since rook endgames are now statistically proven to be not at all boring.


David said...

John Watson makes a very similar case in Secrets of Modern Chess Strategy. He extracts a bunch of statistics from some unnamed database of unstated size, acknowledges that "it's not clear how significant the numbers I've reported are" and then tentatively concludes that "at least compared to other analogous endings, rook endings are not particularly drawish".

Ruy Lopez said...

When I play, all the rook end games are drawn. Except for those that I manage to lose in a drawn position.

Tom Chivers said...

I actually don't remember ever getting down to a rook endgame ---- maybe that's why I've drawn so many games this season?