Tuesday, February 20, 2018

To analyze using a computer part 2

More than 2 decades ago I started to play chess. At that time a lot of scepticism existed about engines. Many avoided them as those things were considered not to play real chess and surely won't be able to teach you anything. This feeling was very widespread as even till a couple of years ago some older players still had never worked with any engine despite playing chess sometimes already for decades.

Such thoughts seem unimaginable for today's young generation used to work with many different chess-programs. Few will still deny that a computer can be very useful to learn chess. Besides we see everyday new programs popping up extending the current applications. Obviously this changed world has created the need for guidance. However as was already valid about 6 years ago see part 1, today still very few or no good literature can be found about this subject. Therefore I expect we will see an increasing demand for special info-sessions about how and which chess-software to use. Recently I gave presentations for LSV and Mechelen. The +60 years old Belgian FM Johan Goormachtigh has offered 5 courses in KGSRL (Gent) which will also include how to work with Chessbase. I guess his content will be limited to the basics considering the target-audience and his rather sporadic use of the tools.

So every ambitious player will today submit his games to the critical evaluations of an engine. Nowadays probably the DroidFish Chess app is the most used engine to get a quick verdict of a game. Almost 100% of the young players possess a smartphone so after their games they will use it to quickly get an assessment of the moves. Unfortunately most of them won't look at the game anymore at home.  2 months ago there was a discussion at chesspub about how useful such homework could still be. Some poster claimed that I am just losing my time by analyzing deeper my games and it would be better to spend that time to other chess-activities like reading chess-books, solving exercises,...

He is definitely not alone with this view. In the past more than one international master told me they were spending much less time at analyzing their played games. So maybe indeed there are better methods to improve at chess. On the other hand it is not a hard proof. Maybe those international masters would've been today (much) stronger if they would have spent more time at analyzing their games. Another argument is that the current top-engines are so strong that it makes no sense to  give an engine a lot of time to analyze the moves. I made a quick experiment to test this statement by running a full analysis using the Fritz 15 interface with below hyper-fast configuration and using the engine Komodo 11.
This means Komodo gets only 1 second per move. Next I use a threshold of 30 so if my move deviates 0,3 pawns from the best move then the engine will comment. Finally for the opening I use as reference-database a correspondence database. For the test I use my game against the Dutch IM Xander Wemmers which was already covered in my article secret as that game contains a number of mistakes. The amazing output is produced in just a couple of minutes by the machine.
[Event "Interclub Borgerhout - Deurne"] [Site "?"] [Date "2017.??.??"] [Round "?"] [White "Wemmers, X."] [Black "Brabo"] [Result "1/2-1/2"] [ECO "A90"] [WhiteElo "2430"] [BlackElo "2310"] [Annotator "Komodo 11 64-bit (1s)"] [PlyCount "98"] [EventDate "2017.??.??"] { [%mdl 8192] A90: Dutch Defence: Miscellaneous and Modern Stonewall (with ... Bd6) } 1.d4 f5 2.g3 Nf6 3.Bg2 e6 4.Nf3 d5 5.O-O Bd6 6.c4 c6 7.Nc3 O-O 8.Qc2 Ne4 9.Rb1 a5 10.a3 Nd7 11.b4 axb4 12.axb4 Ndf6 13.b5 $146 ( 13.c5 Bc7 14.b5 Nxc3 15.Qxc3 Ne4 16.Qc2 cxb5 17.Rxb5 b6 18.cxb6 Bxb6 19.Bf4 Ba6 20.Rb3 Bc4 21.Rb2 Rc8 22.Ra1 Ba5 23.Ra3 Bc7 24.e3 Bxf4 25.exf4 Rf7 26.Ne5 Rfc7 27.Ra1 Bb5 { Brzezinski,B (2221)-Zawadski,A (2178) ICCF 2014 1/2-1/2 } ) ( 13.c5 Bb8 $14 ) 13...Nxc3 14.Qxc3 cxb5 15.c5 { White threatens to win material: c5xd6 } 15...Bc7 ( 15...Ne4 16.Qc2 Bc7 17.Rxb5 $11 ) 16.Rxb5 b6 17.Bf4 ( 17.cxb6!? { must definitely be considered } 17...Bxb6 18.Bf4 $14 ) 17...Ne4 $15 { Black threatens to win material: Ne4xc3 } 18.Qe3 bxc5 19.dxc5 { White has a new passed pawn: c5 } 19...Bd7 { Black threatens to win material: Bd7xb5 } ( 19...Qe8!? $142 { might be a viable alternative } 20.Bxc7 Qxb5 $15 ) 20.Rbb1 $14 Rc8 21.Rfc1 h6 { Secures g5 } ( 21...Bxf4 22.gxf4 Be8 23.Nd4 $16 ) 22.Be5 ( 22.Bxc7 Rxc7 23.Ne5 Bc6 $16 ) 22...Bxe5 ( 22...Be8!? $14 ) 23.Nxe5 $16 Rc7 ( 23...Bc6 24.Qd4 $16 ) 24.f3 Nf6 ( 24...Ng5 25.Rb6 Re8 $16 ) 25.Qd4 ( 25.c6!? $142 Bc8 26.Qd4 $18 ) 25...Bc6 $16 { The bishop blocks c5 } 26.Rb6 { White threatens to win material: Rb6xc6 } 26...Qc8 27.e3 Nd7 28.Bf1 Nxe5 29.Qxe5 Qd7 30.Ra1 Rfc8 31.Raa6 ( 31.Ba6 Rd8 $14 ) 31...Kh8 ( 31...Qe7!? $11 ) 32.Qd6 Qe8 33.Bd3 ( 33.Rb8! Rxb8 34.Qxc7 $16 ) 33...Bd7 $11 34.Ra5 ( 34.Kf2 e5 35.Be2 e4 $11 ) 34...Qf8 ( 34...Qd8 35.Raa6 Rxc5 36.Rb7 $11 ) 35.e4 ( 35.Qxf8+ Rxf8 36.Kf2 Kg8 $11 ) 35...dxe4 36.fxe4 fxe4 ( 36...Qf6 37.Ba6 Qc3 38.Bxc8 Qe1+ 39.Kg2 Qe2+ 40.Kh3 Qg4+ 41.Kg2 Qe2+ 42.Kg1 Qe1+ 43.Kg2 Qe2+ $11 ) 37.Bxe4 { White king safety dropped } ( 37.Qxf8+ Rxf8 38.Bxe4 Rfc8 $14 ) 37...Kg8 { Black king safety dropped } ( 37...Qf6 $142 38.c6 Be8 $11 ) 38.Bd3?? { there were better ways to keep up the pressure } ( 38.Kg2 Qe8 $11 ) 38...Qxd6?? { letting the wind out of his own sails } ( 38...Qf3 $142 { Black would have gained the upper hand } 39.Ra2 Rxc5 $19 ) 39.Rxd6 ( 39.cxd6!? Rc3 40.Bg6 $14 ) 39...Kf7 $11 40.Rd4 Ke7 41.Rc4 Bc6 42.Kf2 Bd5 { Black threatens to win material: Bd5xc4 } 43.Rc2 Kf6 44.Ke3 Ke5 45.Be2 g5 46.Bg4 Rc6 47.Be2 R6c7 { Twofold repetition } 48.Bd3 Rc6 49.Be2 R6c7 1/2-1/2

I and Xander belong to the 1% best players but still at the rate of 1 second per move Komodo 11 could discover all the important mistakes while only running on a very moderate portable. It just shows how much stronger our best engines are today. Even with some very serious handicaps the devices still play much better than us. I made a small study to illustrate how much better this exactly is.
  • Estimated fide-rating of the current top-engine at the rate of 1 minute per move: 3200 (CCRL and SSDF talk about 3400 elo but I think the actual fide-elo can be easily a couple of hundreds lower.)
  • 1 year old top-engine: -52 elo (see my article rise of the machines part 2)
  • Extra ply : 66 elo (see citeseerx.ist.psu.edu)
  • Extra engine running in parallel: - 1 ply (some tests on my laptop)
  • Extra line running in parallel: - 1 ply (some tests on my laptop)
  • Halving the time: - 1 ply (see wikispaces.com/Depth)
Example: 3 year old engine, 2 engines running in parallel, 15 seconds per move, 3 lines running in parallel
  • Start-base : 3200 elo
  • 3 year old engine: - 156 elo
  • 2 engines running in parallel: - 66 elo
  • 15 seconds per move: - 132 elo
  • 3 lines running in parallel:  -132 elo
Analysis are happening at the strength of 2714 elo.

So even if you use an outdated engine in a crippled way then the output is still at the level of a super-grandmaster. Shouldn't that be sufficient for us non professionals? Well I think we should be careful. It does make sense to strive for the highest quality. An opening-analysis is something you want to reuse later so to avoid any rework it is better to do it properly. Besides even killer-novelties can occur on amateur-level.

Also we should admit that the output of an engine is often very difficult to interpret correctly (see above dump). It is one thing to know where the mistakes are made but to understand and correct them is sometimes very hard. Often a lot of extra analyzing is necessary to get a full diagnosis. Check my article the butterfly-effect in which I demonstrated how I discovered by making some deep analysis why a small change of the position creates a big change of the evaluation. A technique which I often use for this kind of work is to let the engine play against itself.

Finally I also believe that working daily with the top-engines will improve your own understanding of chess. You need a tool to detect the small positional errors as it is not enough to just correct the big errors to become a master. Also just looking continuously to strong moves will be very good for your own development. Any trainer will recommend their students to watch and study grandmastergames and engines play even better than any grandmaster. The same comment I make about the lomonosov tablebases. No human is capable to copy the accuracy of the tablebases. Still I do experience that just consulting regularly the tablebases has improved my intuition in many endgames. I can much better estimate which endgames have or do not have serious winning chances.

When I started to analyze my games in 1990 using the assistance of my very first table-computer Mephisto Europa A (playing-strength 1700 elo) I was obliged to spend a lot of time just to achieve a minimum level of accuracy. This need doesn't exist anymore today but I learned in the meanwhile there are other reasons to still analyze deeply your own games. In any case it is much worse for your own development to analyze too little than to analyze too much.

Brabo

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