Analysing your openings repertoire with Fat Fritz

by ChessBase
9/2/2019 – While the idea of Fat Fritz as a self-taught chess AI is tantalizing, many players may wonder why this impacts them if they already have a good engine and they are not grandmasters seeking nearly ineffable edges in their preparation. In the following article, we let a strong amateur study with it for some hours and compare notes with analysis he had made from other engines.

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Not starting from zero

One of the biggest strengths of Fat Fritz over traditional engines is not a simple Elo equation, but in how it evolved. For example, much like when we learn ourselves, the first thing a traditional engine learns is the value of the pieces. Fat Fritz starts with no such information. Instead, it is fed billions of positions (literally) which it studied, and from which it built its understanding of chess. It does not, and cannot, think in terms of material. It sees the chess position solely in terms of win-rate percentages. This in turn frees it of the normal inhibitions based on counting pawns and pieces, since these are only of consequence in how they affect the win-rate.

Why is this so important (other than being an interesting curiosity)? Because very often there will be positions where a traditional engine will see no concrete road to improvement and that are equal in the purest sense, leading to multiple evaluations of 0.00. Fat Fritz may agree that the positions are equal, but it is also capable of seeing which ones tend to lead more often than not to a more successful result. Openings analysis today rarely leads to a concrete win against a well-prepared opponent, so it helps to know which moves or positions have the greatest chance for your opponent to go wrong. 

Since the launch of Fat Fritz we have been conducting a number of experiments, mainly with world-class grandmasters. About that we will speak in separate reports. Today we want to tell you about an experiment we undertook with a 2300 player, whom we gave two hours of access to Fat Fritz. He decided to use the opportunity to check his black repertoire against the Catalan, where he had had problems finding a way to equalise in a critical variation. Analysing with Fat Fritz convinced him that he could achieve equality and so did not need to avoid this particular line. He gave us some of his analysis — a little reluctantly, since he wants to be able to use it in future games.

[Event "Analysis"] [Site "?"] [Date "2019.07.29"] [Round "?"] [White "Catalan 4...Be7"] [Black "Fat Fritz"] [Result "*"] [ECO "E05"] [Annotator "N.N."] [PlyCount "76"] [EventDate "2016.??.??"] 1. d4 d5 2. c4 e6 3. Nf3 Nf6 4. g3 Be7 5. Bg2 O-O 6. O-O dxc4 7. Qc2 a6 8. Qxc4 b5 9. Qc2 Bb7 10. Bd2 Be4 11. Qc1 Bb7 12. a3 Nbd7 13. Ba5 Rc8 14. Nbd2 Qe8 15. b4 Ne4 16. Nxe4 Bxe4 17. Qe3 Bd5 18. Rac1 Bd6 19. Ne5 f5 20. Bxd5 exd5 21. f4 Nf6 22. Rc2 {The position of interest. It looks like White has pressure on the c-file. So I let Fat Fritz look at it and compared its suggestions with that of other engines. [#] Fat Fritz immediately evaluates the position as equal, giving continuations like 22...c6 or 22...h6 (22...Ne4 might be possible as well). Let us look at some of the lines the player worked out with Fat Fritz:} c6 $5 (22... h5 $5 {Fat Fritz considers this an equally strong alternative.} 23. Rfc1 c6 $1 24. Bb6 Ne4 25. Nxc6 (25. Rxc6 Rxc6 26. Nxc6 h4) (25. Bc5 Bxc5 26. bxc5 ( 26. dxc5 a5 27. a4 $2 bxa4 28. b5 cxb5 29. c6 b4 $16 (29... Kh7 $16)))) 23. Rfc1 h5 $1 24. Bb6 Ne4 $1 {A strong pawn sacrifice, immediately spotted by the Fat Fritz cloud engine. It is not the first move of "normal" engines.} (24... Bxe5 $6 25. dxe5 Ne4 26. Bd4 Qg6 27. Kh1 Rfe8 28. a4 {Opening a new front.} Re6 29. axb5 axb5 30. Ra2 Rc7 31. Qf3 Kh7 32. Rg1 {One rook threatens intruding along the a-file, the other one inhibits Black's attack.} Qf7 33. h3 Rh6 34. Kh2 Qe7 35. Qb3 Qe8 36. Ra6 Qe6 37. Ra8 g5 38. Qe3 Rg7 39. fxg5 Rxg5 40. Qf4 $16 (40. Ra7+ Rg7 41. Rxg7+ Kxg7 42. Qf4 {(62) Suba,M (2525)-Psakhis,L (2605), Andorra 1994.})) 25. Nxc6 Qe6 26. h4 Rfe8 27. Kg2 Bf8 28. Ba5 Bd6 (28... Kh7 29. Ne5 Rc4 $1 $11) 29. Ne5 Rc4 $1 $11 30. Nxc4 (30. Qf3 $4 Bxe5 $19 31. fxe5 Rec8 32. Rxc4 dxc4 33. Qxh5 c3 34. Qf3 c2 $19) 30... dxc4 31. Qf3 Qd5 32. e3 Re6 33. Kh2 (33. Qxh5 $4 Ng5+ 34. Kg1 Nf3+ $19 35. Kg2 (35. Kf1 g6 36. Qh6 Bf8 $19) 35... Rxe3) 33... g6 $11 (33... Bb8 $11 34. Ra2 (34. Qxh5 $4 Nf6) 34... g6 ) 34. Qg2 Bb8 35. Ra2 Rc6 36. Rca1 (36. a4 $6 Kf7 37. Rca1 Ke6 38. axb5 axb5 $17) 36... Bd6 (36... Kf7) 37. Rc2 Be7 38. Rac1 Kf7 {with equality.} *

The Fat Fritz evaluation before the key move, and a Stockfish evaluation bar for the whole game

This strong club player's verdict after his session:

I feel much more comfortable analysing with Fat Fritz. I found, in subsequent analysis, that its evaluation of the positions that occurred were more accurate than those of traditional engines, and led me to understand the line better. I was of course looking for the best way to equalize, and found that after the pawn sacrifice on c6 I could reach an impregnable fortress, something that Fat Fritz recognised much faster than Stockfish or Komodo.

Where and how to use Fat Fritz

Just like all the other engines available online for analysis, Fat Fritz can be found in the ChessBase Engine Cloud.  There are several quick ways to do this from within ChessBase 15, or Fritz program (such as Fritz 16, Komodo, or Houdini).

Another very easy way is just to open a game or board position and start an engine with Add Kibitzer.

Add kibitzer

When you do this you get a list of the engines you can open, all in your computer, but under the list is the Cloud button. Just click on it and this way too will take you to the Engine Cloud window.

Load engine

You will then be shown the Engine Cloud window with the list of all the engines available for use.

Engine list

Click or tap to enlarge

Just look for the name Fat Fritz and choose it.

Fat Fritz

For more detailed information, don't hesitate to look at the full guide.


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