Looking for a Random Mover

[Kirill Kryukov]

Hi Kirill,

Try this version: http://www.xs4all.nl/~vermeire/BrutusRND.rar

It is a BrutusRND-version with a UCI-option 'moveRandomly'. It is switched on permanently in this version, now you have your random move generator. You can use all other options that the original chess program had already. SMP, openingbook (don't forget to switch off the book in case you won't want a random opening), pondering (yes, that is random also), all time controls, UCI/WB. Let me know if this is OK for you.

I will probably include the moveRandom UCI-option in my next release as a bonus feature. Then the source will be available too.

Playing against this engine is really fun! I won my first game against a program since years! (OK I admit, I got mated once by the openingbook also...)
Perhaps I can get my son interested in playing chess now. He hates losing.

Best wishes,
Stephan

Hi Stephan! Unfortunately BrutusRND lost on time in game 9 - it never started to play after the external book position was set up. (Completely normal 8 moves opening). Is there anything I can do to help you fix it? Thanks.

Match: Elf 1.3.0 - Brutus_RND_01_UCI.
Time control: 40/4 repeated.
Score: 8-0 after 8 games (stopped after a time loss in game 9).
External book of 8 moves was used (Harry's 8-moves).
GUI: Chessprogram8 (Fritz 8).

[Miguel A. Ballicora]

Random move (RM) would be very weak, but its rating could be estimated indirectly. Another engine could play in a different random way: Simple alpha-beta, but at ply 1 the "eval" score is determined randomly (let's call it RM1). Note that RM would be the equivalent of RM1, but the random process is determined at the root, so RM could be called RM0. So, you can designed engines, RM2, RM3, RM4 etc. all of them weak, but as you increase the plies, they will get stronger (amazing, but this has been proven).

Interesting. Has it been proven by experiment (running test matches)? If so do you have any more information, like time control, number of games, and rating differences? Or has it been proven analytically, like a theorem? Looks interesting, but I can't imagine how many ELO points RM<N> may be stronger than RM?

Yes, it has been measured experimentally, but I do not remember who did. I read about it. Bob must remember.
It makes sense theoretically too. It you search to ply 6 and at the tip you score a random evaluation, you will end up choosing a path that will have the most number of moves from your side, and the least number of moves from the opponent side. The more moves you have, the more times you throw the dice, and the least time your opponent throw the dice. In other words, you search the path with more mobility. That is better than nothing.

Miguel

Also, does any engine implement the RM<N> idea?

So, you can determine a relative rating between RM0... RM6 etc. At this point, you can use RM6 to measure the rating of a weak stable engine, and now you may be on the range to grade the rest.

The only bad or good effect (depends how you look at it) is that the rating scale will be dependent on the time controls. RM strength will be always zero despite it gets relatively weaker at longer time controls. But that is ok, longer time controls give you more "absolute" strength for a normal engine.

Miguel

[Miguel A. Ballicora]

This is a very interesting project, and I once made a similar attempt to extend the rating scale downwards, by analysing the results from the ChessWar promo division. One problem is that the weakest engines are often very unstable. And then they do not behave accordingly to the Elo curve, and analyzing their results as if they do, would extract wrong ratings. (E.g. there is an engine that prints "resign" in stead of "checkmate", so the weaker the opponent, the lower its average score against it.)

I tried to delete as many of obviously disturbing factors (e.g. games where a stronger engine crashed against a weaker one), but it is hard to catch everything. My conclusion (or rather, the result of the analysis) was that the rating of an engine like Pos 1.17 (in its non-random mode!) is slightly below zero, around -50 or so. And Pos 1.17 scores about 75% against a random mover.

The N-ply + random eval is sure to result in a nice set of stable engines that are asymptotically weak. It will take a chain of many of them before you will be able to connect to any decent rating. And connecting the random mover with the poule of decent engines by only one chain will be extremely unreliable. Connecting it through aother chain of engines might lead to a completely different rating. Nevertheless, the ratings of such N-ply random evaluators is of great fundamental interest.

I understood that Bob once did experiments like this. I am not sure about his implementation details. One question is how to evaluate a position where you are checkmated. Is that a normal evaluation, that you assign a random? Or do you assign it minus infinity. (It could be argued that that is cheating of some sort. Especially if you recognize stalemate seperately.) And would you play strictly by legal moves, or by King capture?

I think we could make certain fair assumptions
1) engines that are dumb, but make an honest effort to win or draw (i.e. they do not play suicide chess or resign on move 1 because this is not interesting at all).
2) they know the rules of chess. They recognized a checkmate/stalemates when they are forced to recognize it, for instance, they are in check, they have to move, and they find no legal moves. That means, a 2-ply random search will find a mate in one. They will also claim 50 moves, and 3 fold repetition.
In other words, engines that have zero chess "knowledge", but know the rules and can count.

Miguel

My engine NEG is very stable, and very weak, as it has no search. I especially made it to provide a stable engine in that Elo range. It just captures the piece with the best SEE, or if there is nothing to capture, tries a checking move. It does not know about checkmate. Nevertheless, it has won several games by checkmate in ChessWar. KQQQK is usually enough for it to accidentally win. But it has also won through a kind of fool's mate.

[Stephan Vermeire]

Hi Stephan! Unfortunately BrutusRND lost on time in game 9 - it never started to play after the external book position was set up. (Completely normal 8 moves opening). Is there anything I can do to help you fix it? Thanks.

Match: Elf 1.3.0 - Brutus_RND_01_UCI.
Time control: 40/4 repeated.
Score: 8-0 after 8 games (stopped after a time loss in game 9).
External book of 8 moves was used (Harry's 8-moves).
GUI: Chessprogram8 (Fritz 8).

Hi Kirill,

I will have a look at it and let you know when I found something.

Stephan

[Yannik Snoeckx]

Hi!

It's a very interesting idea.
I have also wondered about such a project.

I agree that the main problem is stability and that the random mover could prove a champ against some buggy engines.
(In this case, buggy means crashing only, not playing major blunders)

I also think that there would be many, many draws, as it is probably easier to reach a draw by repetition, insufficient material or 50 moves rules, than find the only move to checkmate for very weak engines.
(Kind of like super-GM chess reversed)

But, to make it more complicated, and shamelessly asking for a new engine , is the worst program the one that plays random moves or the one that plays bad ones ?
Is there an engine that plays systematically the worst move ?
I'd love to see one and to match it against the random movers !

Best wishes.
YS

[Stephan Vermeire]

Hi Kirill,

Is it correct that the first 8 games were lost by play? Over here it is just running fine. Do you have any kind of debug or logfile for me? I really have no clue what is going on with the current information available.

Stephan

[Kirill Kryukov]

Hi Kirill,

Is it correct that the first 8 games were lost by play? Over here it is just running fine. Do you have any kind of debug or logfile for me? I really have no clue what is going on with the current information available.

Stephan

Hi Stephan, thanks for looking into it. In the first 8 games BrutusRND was checkmated normally, as expected. I will run it through InBetween next time and send you a logfile if it hangs again.

[Stephan Vermeire]

Hi Stephan, thanks for looking into it. In the first 8 games BrutusRND was checkmated normally, as expected. I will run it through InBetween next time and send you a logfile if it hangs again.

That would be great!
Stephan

[H.G.Muller]

I think we could make certain fair assumptions
1) engines that are dumb, but make an honest effort to win or draw (i.e. they do not play suicide chess or resign on move 1 because this is not interesting at all).
2) they know the rules of chess. They recognized a checkmate/stalemates when they are forced to recognize it, for instance, they are in check, they have to move, and they find no legal moves. That means, a 2-ply random search will find a mate in one. They will also claim 50 moves, and 3 fold repetition.
In other words, engines that have zero chess "knowledge", but know the rules and can count.

I would percieve such an engine as very unbalanced. It is almost totally dumb in most of the game, but when a mate happens to get within the horizon, it suddenly starts to play perfect Chess to force it, perhaps even outsmarting a Human GM. That effect alone should convey a huge advantage to the deeper searching engine. Because of its larger "sensor range" it should have a virtually 100% win chance. The draw chances are not very large, as there are plenty of Pawns to push, and repeating positions is quite unlikely. In the end the Pawns will promote, and there will be ample material to effect a checkmate. This effect will even occur without randomization of the eval, evaluating every non-mate position as 0, and randomly choosing between equal scores in the root, and likely completely dominate the effect of the random eval.

I think it would be much more interesting to fore a single random eval in a position where you are checkmated. I.e. in the minimax determination of the best score, not seed with -infinity, but with a random eval, like you would seed in QS with the stand-pat score.

[Miguel A. Ballicora]

I think we could make certain fair assumptions
1) engines that are dumb, but make an honest effort to win or draw (i.e. they do not play suicide chess or resign on move 1 because this is not interesting at all).
2) they know the rules of chess. They recognized a checkmate/stalemates when they are forced to recognize it, for instance, they are in check, they have to move, and they find no legal moves. That means, a 2-ply random search will find a mate in one. They will also claim 50 moves, and 3 fold repetition.
In other words, engines that have zero chess "knowledge", but know the rules and can count.

I would percieve such an engine as very unbalanced. It is almost totally dumb in most of the game, but when a mate happens to get within the horizon, it suddenly starts to play perfect Chess to force it, perhaps even outsmarting a Human GM. That effect alone should convey a huge advantage to the deeper searching engine. Because of its larger "sensor range" it should have a virtually 100% win chance. The draw chances are not very large, as there are plenty of Pawns to push, and repeating positions is quite unlikely. In the end the Pawns will promote, and there will be ample material to effect a checkmate. This effect will even occur without randomization of the eval, evaluating every non-mate position as 0, and randomly choosing between equal scores in the root, and likely completely dominate the effect of the random eval.

I think it would be much more interesting to fore a single random eval in a position where you are checkmated. I.e. in the minimax determination of the best score, not seed with -infinity, but with a random eval, like you would seed in QS with the stand-pat score.

What you say it makes sense, but there is a risk that it will play avoiding the mate. Lets say that there is a mate in one among some legal moves (KQK, for instance). In the search, after makemove() the checkmate, it scores a random number. If the search is set up to ply 6, many of the sibling moves will have higher chances to be played because they will be "throwing the dice" many times, in many nodes. Since the mobility will be much higher compared to the opponent, there is plenty of opportunities to beat the random number obtained after the check mate. The deeper the search, the more chances to avoid the mate. Is that right?

Miguel

[Kirill Kryukov]

Hi Stephan, thanks for looking into it. In the first 8 games BrutusRND was checkmated normally, as expected. I will run it through InBetween next time and send you a logfile if it hangs again.

That would be great!
Stephan

I ran BrutusRND through InBetween, but this time it worked fine. 0-32 vs Elf 1.3.0 as expected, no time losses. I guess it's a rare problem, or may be it's my machine or something else.

[Stephan Vermeire]

I ran BrutusRND through InBetween, but this time it worked fine. 0-32 vs Elf 1.3.0 as expected, no time losses. I guess it's a rare problem, or may be it's my machine or something else.

Very well. Let me know in case you encounter any trouble in the future. Good luck with your project! Are you going to post some of the results? I am very interested in this range of engines.

Best wishes,
Stephan

[Kirill Kryukov]

Hi Stephan,

Thanks! I will let you know if I encounter any more problems with BrutusRND.

My plan is to eventually include Random Mover into my tournament. It will probably take a long time to fill the huge gap between the current lower end of the list and the random mover. Especially since I keep testing stronger engines as well. But at least the Random Mover is now available. Thanks again for providing it!

Best,
Kirill

[H.G.Muller]

Good intermediates to bridge the gap are Chad's Chess, Youk, micro-Max 1.6, Eden 0.13, Xadreco, NEG 0.3d and Pos 1.18. Of course playing time-odds could also be hepful to weaken an engine a few hundred Elo points. (Would not work on NEG, Pos or the random mover, though, as they would not use significant time in the first place.)

[Kirill Kryukov]

Hi H.G.,

Thanks for advice.

Right now I am enforcing Elo difference limit of 500 points in my tourney, but I'll probably lower it to 400 some day. It means that two engines must be at most 400 Elo points apart to play a match. If later I find out that the difference was larger, I remove the games from the database.

My second criteria is that every participant must have at least 16 stronger opponents and at least 16 weaker opponents. (Those at the ends of the list have fewer opponents of course).

Summing these two rules together, I will need about 16 engines per 400 Elo points, or about 4 engines per 100 Elo points, all the way down to the Random Mover. So I'll be looking for some more weak programs in the future.

[Stephan Vermeire]

Perhaps Olivier might help here. Have a look at http://www.open-aurec.com/chesswar/Chesswar015/Chesswar015PSt.htm
These are the lowest entries of the promo-division (all below Youk):

207 YOUK 1.05 1190 FRA -152W +234B -151W -159B -179W =222W +232B =166W +167B -148B -154W 4 49 15.25 1191
208 GFC 2.0_af 1299 ARG +230W -124B -6W +234B -105W -141B -205W -223W =226B +237B =200W 4 48.5 12.25 1146
209 DEEPDUKE 1.1 1116 SUI -192B -98B +215W -165W -178B =169W =212B =225W -186B +235W =206B 4 47.5 15.25 1091
210 KOENIG SCHWARZ 1131 GER -58W +239W -115B -133B -197W +234B -164W +238B -154W -162B +230W 4 47 10.5 1105
211 GEKO 0.4.3 1094 ITA -123B -169W +242W -163B -187W -190B =234W +214W =189B +205B -176W 4 45.5 12.75 1092
212 CS4210 1072 USA -174W -204B +239W =191W -132B -206B =209W -168W +234B -196B +229W 4 43.5 12.25 1075
213 TESTINA 2.2 1255 ITA +239W -105B -110W -108B -220W +235B -231W -202B -230W +227B +233W 4 42 11.5 1072
214 BIGBOOK 3.1 1155 USA -61B +238W -116B -175W -199B -225W -239W -211B +242W +241B +231W 4 38.5 8.5 1018
215 NEG 0.3d 982 NED -183B -205W -209B +242W -168B -224W -223B +240W -187W +239W +237B 4 36.5 7.5 1007
216 EVILKNIGHT III 1213 GER +130W -128B -114W -137B +234W +198B =99W -105B -101W -173B -181W 3.5 56 15.5 1257
217 USURPER 0.5 1101 USA -133W +137B -91W -174B +169W -135B =197W =204W -166B =191B -178W 3.5 54 16.75 1203
218 PYOTR Amateur 0.6_ja 1108 GRE -158B -138W +238B +136W -98B =165W -198B =169W -164B -204W =225B 3.5 51 14.75 1154
219 EVOLCHESS 0.05 1199 IND -135W =227B -71W +231B +138W -156B -176W -179B +228W -185B -175B 3.5 50.5 13.75 1155
220 KNIGHTMARE BP 1140 USA -101B +235W -134B -158W +213B -136W =183B -182W +236B -170W -184B 3.5 50 12.25 1126
221 FIANCHETTO 1060 AUS -157B -186B -72B +238B =189B -166B =191B +187B -194B =190B -205B 3.5 49.5 13.75 1095
222 KISHI 0.1_ja 1099 JPN -136B -178B +241B -155B -180B =207B +235B -104B -201B +236B -186B 3.5 46 10 1031
223 CHESS0 0.3.2 1099 ESP -165B -130B -234W -237W +242W -138B +215W +208B =163W -179B -191W 3.5 44.5 11.5 1061
224 CHEOPS 1.1 1142 CAN -198W +242W -150B -146B -184W +215B =179W -197B +227W -182W -187B 3.5 44.5 10.75 1090
225 MAINSWORTHY 64.01.7 975 ENG -164W -200B -180W +239W -195B +214B -194W =209B -188W =233B =218W 3.5 42.5 11.25 1013
226 OMAR 3.2 1043 ESP -163W =189B -118W -206B -235W +242W -196B =234B =208W +228B -190W 3.5 42 10.25 1000
227 ACE 0.1 968 USA -166B =219W -93B -193W +241B -189W +240B -180W -224B -213W +239W 3.5 41 7.75 1013
228 DENDRON 0.42_ja 1024 USA -179W -196B -168B =241W +233B -201W =202B =195W -219B -226W +240W 3.5 39.5 10 1013
229 ETABETA 7.21 1109 ITA -146W -121B +236W -177B +191W -158W -184B +239W -183B -199W -212B 3 46.5 9.5 1061
230 BELOFTE 0.2.8 1035 BEL -208B -190B -137W =235B +236W -104W -188B =232W +213B -195W -210B 3 45.5 10 1000
231 SHATRANJ 1.17 1042 USA -173B =206B -185W -219W =203B +240W +213B -165W -169B -189W -214B 3 45 10 1043
232 SON OF MAINSWORTHY 5.2.1 1099 ENG -177W -194B +235W -167B -186W =191B -207W =230B +238W -168B -193W 3 44 9.25 1000
233 PRECHESS 0.7.8 1044 BRA -154B -201W -160B =236B -228W +241W -169B +235W -206B =225W -213B 3 42 8.25 1000
234 LAMOSCA 0.10 953 ITA -182B -207W +223B -208W -216B -210W =211B =226W -212W =238B =241W 3 39.5 9.5 1000
235 PULCHESS 0.2i 860 ITA -162W -220B -232B =230W +226B -213W -222W -233B +241W -209B =236W 3 37.5 8.5 1000
236 MICROCHESS 1976 968 USA -184W -188B -229B =233W -230B -239W +242W +237B -220W -222W =235B 3 33.5 6.5 1000
237 AKIBA 0.0.20031118 1039 POL =185W -148B -97W +223B -101B -182W -200B -236W +240B -208W -215W 2.5 46.5 7.75 1000
238 CPP1 0.1038 923 NED -197W -214B -218W -221W +239W -205B +241B -210W -232B =234W -242W 2.5 34 5.5 1000
239 ARICS 0.95a 812 BLR -213B -210B -212B -225B -238B +236B +214B -229B -190B -215B -227B 2 40 7 1000
240 CRUX 5.0m 1162 HUN -159W +241B -156W -198B -164W -231B -227W -215B -237W +242W -228B 2 38.5 3 1000
241 POS 1.20 898 NED -171B -240W -222W =228B -227W -233B -238W +242W -235B -214W =234B 2 33.5 4.25 1000
242 EDEN2 850 ITA -199B -224B -211B -215B -223B -226B -236B -241B -214B -240B +238B 1 36 2.5 1000

I am not sure which engines are freely available though. (Olivier could help you with that one I guess).

Stephan

[Olivier Deville]

Perhaps Olivier might help here. Have a look at http://www.open-aurec.com/chesswar/Chesswar015/Chesswar015PSt.htm
These are the lowest entries of the promo-division (all below Youk):

207 YOUK 1.05 1190 FRA -152W +234B -151W -159B -179W =222W +232B =166W +167B -148B -154W 4 49 15.25 1191
208 GFC 2.0_af 1299 ARG +230W -124B -6W +234B -105W -141B -205W -223W =226B +237B =200W 4 48.5 12.25 1146
209 DEEPDUKE 1.1 1116 SUI -192B -98B +215W -165W -178B =169W =212B =225W -186B +235W =206B 4 47.5 15.25 1091
210 KOENIG SCHWARZ 1131 GER -58W +239W -115B -133B -197W +234B -164W +238B -154W -162B +230W 4 47 10.5 1105
211 GEKO 0.4.3 1094 ITA -123B -169W +242W -163B -187W -190B =234W +214W =189B +205B -176W 4 45.5 12.75 1092
212 CS4210 1072 USA -174W -204B +239W =191W -132B -206B =209W -168W +234B -196B +229W 4 43.5 12.25 1075
213 TESTINA 2.2 1255 ITA +239W -105B -110W -108B -220W +235B -231W -202B -230W +227B +233W 4 42 11.5 1072
214 BIGBOOK 3.1 1155 USA -61B +238W -116B -175W -199B -225W -239W -211B +242W +241B +231W 4 38.5 8.5 1018
215 NEG 0.3d 982 NED -183B -205W -209B +242W -168B -224W -223B +240W -187W +239W +237B 4 36.5 7.5 1007
216 EVILKNIGHT III 1213 GER +130W -128B -114W -137B +234W +198B =99W -105B -101W -173B -181W 3.5 56 15.5 1257
217 USURPER 0.5 1101 USA -133W +137B -91W -174B +169W -135B =197W =204W -166B =191B -178W 3.5 54 16.75 1203
218 PYOTR Amateur 0.6_ja 1108 GRE -158B -138W +238B +136W -98B =165W -198B =169W -164B -204W =225B 3.5 51 14.75 1154
219 EVOLCHESS 0.05 1199 IND -135W =227B -71W +231B +138W -156B -176W -179B +228W -185B -175B 3.5 50.5 13.75 1155
220 KNIGHTMARE BP 1140 USA -101B +235W -134B -158W +213B -136W =183B -182W +236B -170W -184B 3.5 50 12.25 1126
221 FIANCHETTO 1060 AUS -157B -186B -72B +238B =189B -166B =191B +187B -194B =190B -205B 3.5 49.5 13.75 1095
222 KISHI 0.1_ja 1099 JPN -136B -178B +241B -155B -180B =207B +235B -104B -201B +236B -186B 3.5 46 10 1031
223 CHESS0 0.3.2 1099 ESP -165B -130B -234W -237W +242W -138B +215W +208B =163W -179B -191W 3.5 44.5 11.5 1061
224 CHEOPS 1.1 1142 CAN -198W +242W -150B -146B -184W +215B =179W -197B +227W -182W -187B 3.5 44.5 10.75 1090
225 MAINSWORTHY 64.01.7 975 ENG -164W -200B -180W +239W -195B +214B -194W =209B -188W =233B =218W 3.5 42.5 11.25 1013
226 OMAR 3.2 1043 ESP -163W =189B -118W -206B -235W +242W -196B =234B =208W +228B -190W 3.5 42 10.25 1000
227 ACE 0.1 968 USA -166B =219W -93B -193W +241B -189W +240B -180W -224B -213W +239W 3.5 41 7.75 1013
228 DENDRON 0.42_ja 1024 USA -179W -196B -168B =241W +233B -201W =202B =195W -219B -226W +240W 3.5 39.5 10 1013
229 ETABETA 7.21 1109 ITA -146W -121B +236W -177B +191W -158W -184B +239W -183B -199W -212B 3 46.5 9.5 1061
230 BELOFTE 0.2.8 1035 BEL -208B -190B -137W =235B +236W -104W -188B =232W +213B -195W -210B 3 45.5 10 1000
231 SHATRANJ 1.17 1042 USA -173B =206B -185W -219W =203B +240W +213B -165W -169B -189W -214B 3 45 10 1043
232 SON OF MAINSWORTHY 5.2.1 1099 ENG -177W -194B +235W -167B -186W =191B -207W =230B +238W -168B -193W 3 44 9.25 1000
233 PRECHESS 0.7.8 1044 BRA -154B -201W -160B =236B -228W +241W -169B +235W -206B =225W -213B 3 42 8.25 1000
234 LAMOSCA 0.10 953 ITA -182B -207W +223B -208W -216B -210W =211B =226W -212W =238B =241W 3 39.5 9.5 1000
235 PULCHESS 0.2i 860 ITA -162W -220B -232B =230W +226B -213W -222W -233B +241W -209B =236W 3 37.5 8.5 1000
236 MICROCHESS 1976 968 USA -184W -188B -229B =233W -230B -239W +242W +237B -220W -222W =235B 3 33.5 6.5 1000
237 AKIBA 0.0.20031118 1039 POL =185W -148B -97W +223B -101B -182W -200B -236W +240B -208W -215W 2.5 46.5 7.75 1000
238 CPP1 0.1038 923 NED -197W -214B -218W -221W +239W -205B +241B -210W -232B =234W -242W 2.5 34 5.5 1000
239 ARICS 0.95a 812 BLR -213B -210B -212B -225B -238B +236B +214B -229B -190B -215B -227B 2 40 7 1000
240 CRUX 5.0m 1162 HUN -159W +241B -156W -198B -164W -231B -227W -215B -237W +242W -228B 2 38.5 3 1000
241 POS 1.20 898 NED -171B -240W -222W =228B -227W -233B -238W +242W -235B -214W =234B 2 33.5 4.25 1000
242 EDEN2 850 ITA -199B -224B -211B -215B -223B -226B -236B -241B -214B -240B +238B 1 36 2.5 1000

I am not sure which engines are freely available though. (Olivier could help you with that one I guess).

Stephan

Hi all

All of them but Etabeta are freely available. Some of those ones are very buggy though and I suppose Kirill is looking for stable engines.

From this list the stable ones are (if my memory does not fail) Youk, DeepDuke, Geko, NEG, Pyotr, Mainsworthy (and the other engines by the same author), ACE, Akiba and POS. They may lose on time if the time control is a bit fast, but at least they won't crash.

Olivier

[Guenther Simon]

Perhaps Olivier might help here. Have a look at http://www.open-aurec.com/chesswar/Chesswar015/Chesswar015PSt.htm
These are the lowest entries of the promo-division (all below Youk):

222 KISHI 0.1_ja 1099 JPN -136B -178B +241B -155B -180B =207B +235B -104B -201B +236B -186B 3.5 46 10 1031

I am not sure which engines are freely available though. (Olivier could help you with that one I guess).

Stephan

Hi all

All of them but Etabeta are freely available. Some of those ones are very buggy though and I suppose Kirill is looking for stable engines.

From this list the stable ones are (if my memory does not fail) Youk, DeepDuke, Geko, NEG, Pyotr, Mainsworthy (and the other engines by the same author), ACE, Akiba and POS. They may lose on time if the time control is a bit fast, but at least they won't crash.

Olivier

I have never heard about Kishi and I also did not find it on Jims official site, thus I have
some doubts about it being freely available, Olivier?

Best regards,
Guenther

[H.G.Muller]

Many of those engines are not usable. At least not without altering the underlying theory about rating, and the extraction procedure that follows from it. Some of these engines are so weak because they forfeit the majority of their games on time, and would do that irrespective of how weak the opponent is. When they are lucky enough not to crash, they can play quite good. So they might score 25% against a 1200-Elo opponent, 25% wins and 75% forfeits. But when you would pit them against a random mover, (say that has 0 Elo on the same scale), they would still score the same 25%. Scores between engines like that will not behave according to the Elo curve, so that it is questionable if Elo rating even is a meaningful concept for them.

[Olivier Deville]

Perhaps Olivier might help here. Have a look at http://www.open-aurec.com/chesswar/Chesswar015/Chesswar015PSt.htm
These are the lowest entries of the promo-division (all below Youk):

222 KISHI 0.1_ja 1099 JPN -136B -178B +241B -155B -180B =207B +235B -104B -201B +236B -186B 3.5 46 10 1031

I am not sure which engines are freely available though. (Olivier could help you with that one I guess).

Stephan

Hi all

All of them but Etabeta are freely available. Some of those ones are very buggy though and I suppose Kirill is looking for stable engines.

From this list the stable ones are (if my memory does not fail) Youk, DeepDuke, Geko, NEG, Pyotr, Mainsworthy (and the other engines by the same author), ACE, Akiba and POS. They may lose on time if the time control is a bit fast, but at least they won't crash.

Olivier

I have never heard about Kishi and I also did not find it on Jims official site, thus I have
some doubts about it being freely available, Olivier?

Best regards,
Guenther

Hi Guenther

Kishi is a very lousy engine that can play only with black pieces. It was announced once at CCC, Jim compiled it and posted a download link.

Of course very few people will find any interest for such an engine

Olivier