146 tactics problems from Bobby Fischer games

[ogam]

I've analysed with Stockfish 1.9.1 (10 sec per move) 826 chess games of Bobby Fischer and I've found 146 interesting tactical positions to solve.
You can found and interactively solve these puzzles here:

http://www.ideachess.com/chess_tactics_ ... ics_n/8464

problems are numbered from 8464 to 8609. Under the board you can read from which Fischer game the problem came from.

Gianluca

[Albert Silver]

I've analysed with Stockfish 1.9.1 (10 sec per move) 826 chess games of Bobby Fischer and I've found 146 interesting tactical positions to solve.
You can found and interactively solve these puzzles here:

http://www.ideachess.com/chess_tactics_ ... ics_n/8464

problems are numbered from 8464 to 8609. Under the board you can read from which Fischer game the problem came from.

Gianluca

The concept is fun, but it seems it won't accept a solution unless it is precisely the same as the one it found. For example, in the very first one I tried:

[D]r5k1/1p2pp1p/3p2pQ/1p3P1P/q5P1/P1P5/1P1Rr3/1K5R b - -

I played 1...Qe4+ (obviously) and after 2.Ka2 Rxd2 which is easily winning. After 3.Qxd2 (forced since 3.hxg6 Rxa3+ is mate) Qxh1 is game over. After playing out my solution, and up a rook, it told me to "retry".

[ogam]

It accepts all solutions that at the end of the number of prefixed moves lead to the maximum gain in material.
In this case the solution found by the engine after 7 moves lead to a material advantage of 700 (captured Queen + 2 Pawn vs captured Rock). Your solution if end up with a Rock of advantage is evaluated 500 so inferior to the proposed one.

I see the following possibilities:
- The applet can say "this is a good solution but not the best retry" because the solution found lead to an advantage for example >= 200 points but inferior tho the best one.
- Accept all solutions that lead to an advantage for example of at least 200 points from the initial position.
- Accept only the solutions that lead to the maximum material gain in the prefixed moves (as is now).



Zuril

[Matthias Gemuh]

It accepts all solutions that at the end of the number of prefixed moves lead to the maximum gain in material.
In this case the solution found by the engine after 7 moves lead to a material advantage of 700 (captured Queen + 2 Pawn vs captured Rock). Your solution if end up with a Rock of advantage is evaluated 500 so inferior to the proposed one.

I see the following possibilities:
- The applet can say "this is a good solution but not the best retry" because the solution found lead to an advantage for example >= 200 points but inferior tho the best one.
- Accept all solutions that lead to an advantage for example of at least 200 points from the initial position.
- Accept only the solutions that lead to the maximum material gain in the prefixed moves (as is now).

Zuril

It makes sense to assume that all solutions with an advantage of ROOK or more are equally good. They all win.

Matthias.

[ogam]

An handy link to the tactics problems

http://www.ideachess.com/collection/v/fischer

Gianluca

[ogam]

It makes sense to assume that all solutions with an advantage of ROOK or more are equally good. They all win.
Matthias.

Right. But if in a tactical position the color that has to move has already an advantage of 400 points for example and can with the best variant gains other 500 points if I apply the rule of the rook advantage the player can capture a pawn and the solution will be considered correct. The player wins the game but he don't see the tactical motif.
Anyway probably a tactics problem where one side is already in so great material advantage is not interesting...

Ciao, Gianluca

[Albert Silver]

It makes sense to assume that all solutions with an advantage of ROOK or more are equally good. They all win.
Matthias.

Right. But if in a tactical position the color that has to move has already an advantage of 400 points for example

He only has this so called advantage because of the rook win. If you move the queen to a6 for example, where there is no rook win, tell me what 4.xx advantage there is. Thus the win of the rook is the decisive factor in the winning advantage.

[EroSennin]

Problems are good but oh boy the solutions suck. So many simple human wins are disregarded. Also exactly the same moves are not allowed either.
How the solution is presented sucks too. And the error sign should be shown immediately.
Check this problem for understanding:
http://www.ideachess.com/problems/view/t/6068

After 1.Rxg4 Rc1 2.Kh2 is the only allowed move. But Kg2 is the same. Also after 2.Kg2 Rxf2 3.Kxf2 is just an easier way to win for humans Qxg4 4.Qh7 Kf8 5.Qxh6 Ke8 6.Qxc1 Qxe4 7.Qe3.

[ogam]

Check this problem for understanding:
http://www.ideachess.com/problems/view/t/6068

This is the link to the problem that works for unregistered users:

http://www.ideachess.com/chess_tactics_ ... ics_n/6068

[ogam]

He only has this so called advantage because of the rook win. If you move the queen to a6 for example, where there is no rook win, tell me what 4.xx advantage there is. Thus the win of the rook is the decisive factor in the winning advantage.

I was not speaking about this specific problem but in general in order to find a rule to implement in the software to evaluate if a solution is correct or not.