jd1 wrote:It surely depends on just how unbalanced the position is.
To take it to the extreme, if the position is easily won even a weak player can score 50% against a much stronger opponent.
On the other hand, I do remember some studies here showing that unbalanced openings increased the % of wins the stronger engine could score against a weaker opponent.
I suppose it's partly because a lot of openings are very drawish at the higher levels of computer chess. Also unbalanced openings gives the stronger engine to show its superiority by winning the favourable position and holding the return game to a draw, whereas with a perfectly equal opening the weaker engine is likely to get two draws.
Draws in the variant CrazyHouse only run about 4% ( original subject matter).
Enormous thanks to SFZH programmers. They realized one of my dreams. I posted a few threads a few years ago (in Winboard forum and here under another account if I remember well) asking if someone could make SF play zh or improve Sunsetter.
I love zh (more than chess) and I plan to teach my 1 year old son zh before chess.
So thanks again Daniel, Fabian and the others.
Fabian Fichter wrote:
Strongly unbalanced positions usually decrease the Elo difference if the difference in playing strength is big as it helps the weaker engine to win some games.
??
Why do you think this?
I think just the opposite.
To a certain point the higher the unbalancing in the start positions the higher the chance of the stronger engine to win the competition with higher rate and higher Elo gain.
I think that crazyhouse is a completely different story from standard chess, since in crazyhouse the draw rate is basically negligible. This means that starting from a balanced position the weaker engine has almost no chance to escape with a draw, so it has to outplay the stronger engine. If the positions are more imbalanced, it is much easier for the weaker engine to sometimes score a lucky win due to favorable opening positions. I do not have much data to support this, but I would be surprised if the effect were the opposite.
Nordlandia wrote:How do i contribute CPU to Crazyhouse SF?
If you are familiar of how to contribute CPU time to official fishtest, it is quite easy. Instead of using the worker code from Gary's repository, just use my fork https://github.com/ianfab/fishtest and get an account for multi-variant fishtest on http://35.161.250.236:6543/signup.
Isaac wrote:Enormous thanks to SFZH programmers. They realized one of my dreams. I posted a few threads a few years ago (in Winboard forum and here under another account if I remember well) asking if someone could make SF play zh or improve Sunsetter.
I love zh (more than chess) and I plan to teach my 1 year old son zh before chess.
So thanks again Daniel, Fabian and the others.
Thanks, nice to hear that you like it.
Before I started to implement the crazyhouse rules about a year ago I did not really believe I would get it to work, but when I seriously started it, a first implementation (with dozens of bugs...) was to my surprise finished within a couple of hours. The official Stockfish code is in my opinion very well readable and structured, otherwise it would have been much harder to do this. It then took some time to stabilitze the implementation together with Daniel, but the performance without any crazyhouse-specific search or evaluation adaptions and still some bugs was already quite surprising. It is remarkable how well Stockfish's search techniques work for many variants that are quite different from standard chess.
It is a completely separate fishtest instance, so you have to create a new account under http://35.161.250.236:6543/signup (you can of course use the same username if you like) to be able to connect.
The difficulty of "teaching" Stockfish a new variant heavily depends on how different a variant is from standard chess. Additional winning conditions (king of the hill, three-check) are quite easy to implement, whereas differences in the rules that change the move generation (e.g., atomic, giveaway, losers, crazyhouse) are more challenging. The two kings variant should be feasible to implement, but it would take some effort especially regarding the logic for pins, checks and check evasions. Since it is not a very popular variant, it does not have a high priority for me. Maybe I (or someone else) will implement it in the future, but I do not expect it to be any time soon.
