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Comments by DerekNalls
Muller: Please investigate this potentially serious bug I may have discovered while testing Joker80 under Winboard F ... Bugs, Bugs, Bugs! http://www.symmetryperfect.com/pass I am having a hard time with software today.
'Human vs. engine play is virtually untested. Did you at any point of the game use 'undo' (through the WinBoard 'retract move')?' Yes. Many of us error-prone humans use it frequently. ________________________________________________ 'This is indeed something I should fix but the current work-around would be not to use 'undo'.' Makes sense to me. I can avoid using the 'retract move' command altogether. ________________________________________________________ 'I could make a Joker80 version that reads the piece base values from a file 'joker.ini' at startup. Then you could change them to anything you want to test, without the need to re-compile. Would that satisfy your needs?' Yes, better than I ever imagined. Thank you!
Everything is working fine. Thank you! I now have 12 instances of the Joker80 program running in various sub-directories of Winboard F with the 'winboard.ini' file set to conveniently initiate any desired standard or special material values for the CRC models by Muller, Scharnagl and Nalls. In the first test, I am going to attempt to find a playtesting time where a distinct seperation in playing strength occurs between the standard Muller model wherein the rook is 1 pawn more valuable than the bishop and a special Muller model wherein the rook is 2 pawns more valuable than the bishop. If I successfully find a playtesting time that is survivable by humans, then we can hopefully establish a tentative probability as to which CRC model plays decisively better after a few-several games. At par 100 (for the pawn), the bishop is at 459 under both models with the rook at 559 under the standard Muller model and 659 under the special Muller model. I want to playtest a special Muller model with a rook value 2.00 pawns higher than the bishop because the Nalls model has a rook value 2.19 pawns higher than the bishop and the Scharnagl model has a rook value 1.94 pawns higher than the bishop (for an average of 2.06 pawns). Since I am attempting to test for such a small difference in the material value of only one type of piece (the rook), I have doubts that I will be able to obtain conclusive results. In any case ... If I obtain conclusive results, then very long time controls will surely be required to produce them.
Of course, I would bet anything that there are no 1:1 exchanges supported under the standard Muller CRC model that could cause material losses. If that were the case, yours would not be one of the three most credible CRC models under close consideration. In fact, even your excellent Joker80 program would play poorly if stuck with using faulty CRC piece values. Obviously, the longer the exchange, the rarer its occurrence during gameplay. The predominance of simple 1:1 exchanges over even the least complicated, 1:2 or 2:1 exchanges, in gameplay is large although I do not know the stats. In fact, there is a certain 1:2 or 2:1 exchange I am hoping to see that is likely to support my contention that the Muller rook value should be higher: the 1 queen for 2 rooks or 2 rooks for 1 queen exchange. Please recall that under the standard Muller model, this is an equal exchange. However, under asymmetrical playtesting of comparable quality to and similar to that I used to confirm the correctness of your higher archbishop value, I played numerous CRC games at various moderate time controls where the player without 1 queen (yet with 2 rooks) defeated the player without 2 rooks (yet with 1 queen). Ultimately, a key mechanism to conclusive results is that while the standard Muller model is neutral toward a 2 rook : 1 queen or 1 queen : 2 rook exchange, the special Muller model regards its 1 queen as significantly less valuable than 2 rooks of its opponent. Consequently, this contrast in valuation could be played into ... and we would see who wins. I am actually pleased that you are a realist who shares my pessimism in this experiment. In any case, low odds do not deter a best effort to succeed. The main difference between us is that you calculate your pessimism by extreme statistical methods whereas I calculate my pessimism by moderate probabilistic methods. I remain hopeful that eventually I will prove to you that the method Scharnagl & I developed is occasionally productive.
Muller:
Please confirm that these are legal values for the 'winboard.ini' file.
/firstChessProgramNames={'C:\winboard-F\Joker80\w\M-st\w-M-st 22
P100=353=459=559=1029=1059=1118'
'C:\winboard-F\Joker80\w\M-sp\w-M-sp 22
P100=353=459=659=1029=1059=1118'
'C:\winboard-F\Joker80\w\S-st\w-S-st 22
P100=306=363=557=702=912=960'
'C:\winboard-F\Joker80\w\S-sp\w-S-sp 22
P100=306=363=557=866=912=960'
'C:\winboard-F\Joker80\w\N-st\w-N-st 22
P100=308=376=594=940=958=1031'
'C:\winboard-F\Joker80\w\N-sp\w-N-sp 22
P100=308=376=594=940=958=1031'
'C:\winboard-F\TJchess\TJChess10x8'
}
/secondChessProgramNames={'C:\winboard-F\Joker80\b\M-st\b-M-st 22
P100=353=459=559=1029=1059=1118'
'C:\winboard-F\Joker80\b\M-sp\b-M-sp 22
P100=353=459=659=1029=1059=1118'
'C:\winboard-F\Joker80\b\S-st\b-S-st 22
P100=306=363=557=702=912=960'
'C:\winboard-F\Joker80\b\S-sp\b-S-sp 22
P100=306=363=557=866=912=960'
'C:\winboard-F\Joker80\b\N-st\b-N-st 22
P100=308=376=594=940=958=1031'
'C:\winboard-F\Joker80\b\N-sp\b-N-sp 22
P100=308=376=594=940=958=1031'
'C:\winboard-F\TJchess\TJChess10x8'
}As I moved to renormalize all of the values used in Joker80 (written into the 'winboard.ini' file) with the pawn at a par of 85 points, I looked at my notes again. They reminded me that your use of the 'bishop pair' refinement (with a bonus of 40 points) ramifies that the material value of the rook is either 1.00 pawns or 1.47 pawns greater than the material value of the bishop in CRC, depending upon whether or not only one bishop or both bishops, respectively, remain in the game. At that point, I realized that I would be attempting to playtest for a discrepancy that I know from experience is just too small to detect even at very long time controls. So, this planned test has been cancelled. I am not implying that this matter is unimportant, though. I remain concerned for the standard Muller model whenever it allows the exchange of its 2 rooks for 1 queen belonging to its opponent.
Muller:
Please have another look at this except from my 'winboard.ini' file.
There are standard and special versions of piece values by Muller,
Scharnagl & Nalls for the white and black players renormalized to pawn =
85 points.
The special version of the Muller model has a rook value exactly 85 points
or 1.00 pawn higher than the standard version.
The special version of the Scharnagl model has an archbishop value (736
points) at appr. 95% of the archbishop value (775 points) instead of 597
points at appr. 77% for the standard version.
The special version of the Nalls model is identical to the standard
version until some test is needed and planned.
Since I assume that the 'bishop pairs bonus' is hardwired into Joker80,
40 points has been subtracted from the model-independant, material values
of the bishop under all three models. Is this correct?
_____________________________________________________
/firstChessProgramNames={'C:\winboard-F\Joker80\w\M-st\w-M-st 22
P85=300=350=475=875=900=950'
'C:\winboard-F\Joker80\w\M-sp\w-M-sp 22
P85=300=350=560=875=900=950'
'C:\winboard-F\Joker80\w\S-st\w-S-st 22
P85=260=269=474=597=775=816'
'C:\winboard-F\Joker80\w\S-sp\w-S-sp 22
P85=260=269=474=736=775=816'
'C:\winboard-F\Joker80\w\N-st\w-N-st 22
P85=262=279=505=799=815=876'
'C:\winboard-F\Joker80\w\N-sp\w-N-sp 22
P85=262=279=505=799=815=876'
'C:\winboard-F\TJchess\TJChess10x8'
}
/secondChessProgramNames={'C:\winboard-F\Joker80\b\M-st\b-M-st 22
P85=300=350=475=875=900=950'
'C:\winboard-F\Joker80\b\M-sp\b-M-sp 22
P85=300=350=560=875=900=950'
'C:\winboard-F\Joker80\b\S-st\b-S-st 22
P85=260=269=474=597=775=816'
'C:\winboard-F\Joker80\b\S-sp\b-S-sp 22
P85=260=269=474=736=775=816'
'C:\winboard-F\Joker80\b\N-st\b-N-st 22
P85=262=279=505=799=815=876'
'C:\winboard-F\Joker80\b\N-sp\b-N-sp 22
P85=262=279=505=799=815=876'
'C:\winboard-F\TJchess\TJChess10x8'
}'If I were you, I would normalize all models to Q=950 but then replace the pawn value everywhere by 85.' Since this is what you (the developer of Joker80) recommend as optimum, this is what I will do. Are you sure that replacing any pawn values different than 85 points after renormalization to queen = 950 points still renders an accurate and complete representation, more or less, of the Scharnagl and Nalls models? At par of queen = 950 points, the pawn value in the Nalls model is not represented as being only 92.19% as high as that in the Muller model and the pawn value in the Scharnagl model is not represented as being only 98.95% as high as that in the Muller model. Thru it all ... If a perfect representation is not quite possible, I can accept that without reservation. __________________________________ 'I don't think you could say then that you deviate from the model as the models do not really specify which type of Pawn they use as a standard.' Correctly calculating pawn values at the start of the game (much less, throughout the game) requires finesse as it is indeed a complex issue. In fact, its excessively complexity is the reason my 66-page paper on material values of pieces is silent in the case of calculating pawn values in FRC & CRC. Instead, someone needs to read an entire book from an outside source about calculating the material values of the pieces in Chess to sufficiently understand it. Personally, I am content with the test situation as long as Joker80 handles all pawns under all three models initially valued at 85 points as fairly and equally as realistically possible. I cannot speak for Reinhard Scharnagl at all, though. ________________________________________________ 'The way you did it now would make the first Bishop to be traded of the value the model prescribes, but would make the second much lighter. If you would subtract half the bonus, then on the average they would be what the model prescribes.' Now, I understand better. It makes sense. [I am glad I asked you.] Yes, I will subtract 20 points (1/2 of the 'bishop pair bonus') from the model-independant, material values for the bishop under the Scharnagl & Nalls models.
Muller:
Here is my latest revision to my 'winboard.ini' file.
Are these piece values acceptable to you?
Do you think these piece values will work smoothly with Joker80 running
under Winboard F yet remain true to all three models?
______________________________________________________
/firstChessProgramNames={'C:\winboard-F\Joker80\w\M-st\w-M-st 22
P85=300=350=475=875=900=950'
'C:\winboard-F\Joker80\w\M-sp\w-M-sp 22
P85=300=350=560=875=900=950'
'C:\winboard-F\Joker80\w\S-st\w-S-st 22
P85=302=339=551=694=902=950'
'C:\winboard-F\Joker80\w\S-sp\w-S-sp 22
P85=302=339=551=857=902=950'
'C:\winboard-F\Joker80\w\N-st\w-N-st 22
P85=284=326=548=866=884=950'
'C:\winboard-F\Joker80\w\N-sp\w-N-sp 22
P85=284=326=548=866=884=950'
'C:\winboard-F\TJchess\TJChess10x8'
}
/secondChessProgramNames={'C:\winboard-F\Joker80\b\M-st\b-M-st 22
P85=300=350=475=875=900=950'
'C:\winboard-F\Joker80\b\M-sp\b-M-sp 22
P85=300=350=560=875=900=950'
'C:\winboard-F\Joker80\b\S-st\b-S-st 22
P85=302=339=551=694=902=950'
'C:\winboard-F\Joker80\b\S-sp\b-S-sp 22
P85=302=339=551=857=902=950'
'C:\winboard-F\Joker80\b\N-st\b-N-st 22
P85=284=326=548=866=884=950'
'C:\winboard-F\Joker80\b\N-sp\b-N-sp 22
P85=284=326=548=866=884=950'
'C:\winboard-F\TJchess\TJChess10x8'
}Originally, I planned two 'internal playtests'. [By this self-invented term I mean playtests of the standard model of a person against a special model that I have compelling reasons to think may be superior by a provable margin.] The first planned test involves the standard CRC model of Muller against a special CRC model with a higher, closer-to-conventional rook value. Upon closer examination, I suspected that the discrepancy was possibly too small to be detected even with very long time controls. So, I announced that this test was cancelled. Notwithstanding, I may change my mind and return to this unsolved mystery if Joker80 demonstrates unusually-high aptitude as a playtesting tool. This might require very deep runs of moves with a completion time of a few weeks to a few months per pair of games to achieve conclusive results. The second planned test involves the standard CRC model of Scharnagl against a special CRC model with a higher, unconventional archbishop value. Scharnagl currently assigns the archbishop with a material value of appr. 77% that of the chancellor in his standard CRC model. Muller currently assigns the archbishop with a material value of greater than 97% that of the chancellor in his standard CRC model. Nalls currently assigns the archbishop with a material value of lesser than 98% that of the chancellor in his standard CRC model. I devised a special CRC model using identical material values for every piece in the standard CRC model by Scharnagl except that it assigns the archbishop with a material value of exactly 95% that of the chancellor (18% or 1.65 pawns higher). [Note that this figure is slightly more moderate than those by Muller & Nalls.] A discrepancy this large should be detectable at short-moderate time controls. This test is now underway. If either of these tests are successful at establishing or implicating a probability that the special models play stronger than the standard models, then revisions to the standard models may occur. At that juncture, we would be ready to begin 'external playtests'. [By this self-invented term I mean playtests of the standard models of different persons against one another.]
I have recently been sufficiently convinced via asymmetrical playtesting (still underway) that the 2 rooks : 1 queen advantage in material values is appr. the same in CRC as in FRC. [I used to think it was higher in CRC.] Consequently, I revised my model (again) and my CRC piece values: universal calculation of piece values http://www.symmetryperfect.com/shots/calc.pdf CRC material values of pieces http://www.symmetryperfect.com/shots/values-capa.pdf FRC material values of pieces http://www.symmetryperfect.com/shots/values-chess.pdf This change was implemented by raising the value of the queen in CRC- not by lowering the value of the rook. revised Joker80 values Nalls standard CRC model P85=268=307=518=818=835=950
'If the result would be different from playing at a a more 'normal' TC, like one or two hours per game, it would only mean that any conclusions you draw on them would be irrelevant for playing Chess at normal TC.' Conclusions drawn from playing at normal time controls are irrelevant compared to extremely-long time controls. It is desirable to see what secrets can be discovered from a rarely viewed vantage of extremely well-played games. Are not you interested at all to analyze move-by-move games played better than almost any pair of human players are capable? You do not seem to understand that I, too, am discontent with the probability of a small number of wins or losses in a row. This is a compensation that reduces the chance that the games were randomly played to the greatest extent attainable and consequently, the winner or loser randomly determined. _____________________________ '... playing 2 games will be like flipping a coin.' Correction- Playing 1 game will be like flipping a coin ... once. Playing 2 games will be like flipping a coin ... twice. The chance of getting the same flip (heads or tails) twice-in-a-row is 1/4. Not impressive but a decent beginning. Add a couple or a few or several consecutive same flips and it departs 'luck' by a huge margin. _______________________________________________________________ 'The result, whatever it is, will not prove anything, as it would be different if you would repeat the test. Experiments that do not give a fixed outcome will tell you nothing, unless you conduct enough of them to get a good impression on the probability for each outcome to occur.' I have wondered why the performance of computer chess programs is unpredictable and varied even under identical controls. Despite their extraordinary complexity, I think of computer hardware, operating systems and applications (such as Joker80) as deterministic. The details of the differences in outcomes do not concern me. In fact, to the extent that your remarks are true, they will support my case if my playtesting is successful that the unlikelihood of achieving the same outcome (i.e., wins or losses for one player) is extreme. I am pleased to report that I estimate it will be possible, over time, to generate enough experiments using Joker80 to have meaning for a high-quality, low-quantity advocate (such as myself) and even a moderate-quality, moderate-quantity advocate (such as Scharnagl). As for a low-quality, high-quantity advocate (such as you), you will always be disappointed as you are impossible to please.
'Actually the chance for twice the same flip in a row is 1/2.' ______________________________________________________ Really? You obviously need a lesson on probability. Let us start with elementary stuff. Mathematical Ideas fifth edition Miller & Heeren 1986 It is an old college textbook from a class I took in the mid-90's. [Yes, I passed the class.] ______________________ It says interesting things such as- 'The relative frequency with which an outcome happens represents its probability.' 'In probability, each repetition of an experiment is a trial. The possible results of each trial are outcomes.' ____________________________________________ An example of a probability experiment is 'tossing a coin'. Each 'toss' (trial of the experiment) has only two equally-possible outcomes, 'heads' or 'tails' ... assuming the condition that the coin is fair (i.e., not loaded). probability = p heads = h tails = t number of tosses = x addition = + involution = ^ [This is a substitute upon a single line for superscript representation of an exponent to the upper right of a base.] probability of heads = p(h) probability of tails = p(t) p(h) is a base. p(t) is a base. x is an exponent. p(h) = 0.5 p(t) = 0.5 _________________ What follows are examples of the chances of getting the same result upon EVERY consecutive toss. 1 time x = 1 p(h) ^ x = 0.5 ^ 1 = 0.5 p(t) ^ x = 0.5 ^ 1 = 0.5 Note: In this case only ... p(h) + p(t) = 1.0 2 times x = 2 p(h) ^ x = 0.5 ^ 2 = 0.25 p(t) ^ x = 0.5 ^ 2 = 0.25 3 times x = 3 p(h) ^ x = 0.5 ^ 3 = 0.125 p(t) ^ x = 0.5 ^ 3 = 0.125 Etc ... ______________________ By a function that is the inverse of successive exponents of base 2, the chance for consecutive tosses to yield the same result rapidly becomes extremely small. When this occurs, there are only two possibilities- 'random good-bad luck' or an unfair advantage-disadvantage exists (i.e., 'the coin is loaded'). The sum of these two possibilities always equals 1. random luck (good or bad) = l unfair (advantage or disadvantage) = u luck (heads) = l(h) luck (tails) = l(t) unfair (heads) = u(h) unfair (tails) = u(t) p(h) ^ x = l(h) p(t) ^ x = l(t) l(h) + u(h) = 1 l(t) + u(t) = 1 Therefore, as the chances of 'random good-bad luck' become extremely low in the example, the chances of an advantage-disadvantage existing for 'one side of the coin' or (if you follow the analogy) 'one side of the gameboard' or 'one player' or 'one set of piece values' become likewise extremely high. Only if it can be proven that an advantage-disadvantage does not exist for one player, then can it be accepted that the extremely unlikely event by 'random good-bad luck' is indeed the case. It is essential to understand that random good luck or random bad luck cannot be consistently relied upon. From this fact alone, firm conclusions can be responsibly drawn with a strong probability of correctness. ____________________________________________________________ 1 time x = 1 p(h) ^ x = 0.5 u(h) = 0.5 p(t) ^ x = 0.5 u(t) = 0.5 2 times x = 2 p(h) ^ x = 0.25 u(h) = 0.75 p(t) ^ x = 0.25 u(t) = 0.75 3 times x = 3 p(h) ^ x = 0.125 u(h) = 0.875 p(t) ^ x = 0.125 u(t) = 0.875 Etc ...
'... in Joker the source of indeterminism is much less subtle: it is programmed explicitly.' This renders Joker80 totally unsuitable for my playtesting purposes. [I am just relieved that you told me this bizarre fact now before I invested large amounts of computer time and effort.] It is critically important that any AI program attempt (to its greatest capability) to pinpoint the single, very best possible move in the time allowed upon every move in the game even if this means that it would often-sometimes repeat an identical move from an identical position. Do not you realize that forcing Joker80 to do otherwise must reduce its playing strength significantly from its maximum potential?
Well, when you said ... 'Actually the chance for twice the same flip in a row is 1/2.' ... that was vague and misleading. I thought you meant 'heads' twice OR 'tails' twice equals a chance of 1/2 instead of the sum of 'heads' twice AND 'tails' twice equals a chance of 1/2. Since English is a second language to you, of course I will overlook this minor mis-communication and even apologize for implicitly accusing you of incompetence. However, you should expect that you will draw critical reactions from others when you have previously, falsely, explicitly accused them of incompetence in a subject matter.
The reason you have never been able find any correlation between winning probabilities for one army and time controls [contrary to the experiences of people using other AI programs] in asymmetrical playtests using Joker80 is that you have destructively randomized the algorithm within your program to such an extent that it fails to measurably improve the quality of its moves as a function of time or plies completed. A program with serious problems of this nature may do well in speed chess but at truly long time controls against quality programs that improve as they should with time or plies per move, it cannot consistently win. I have two useful, important pieces of news for you: 1. All of the statistical data you have generated using Joker80 (appr. 20,000+ games) is corrupt. It must all be thrown out and started over from scratch after you repair Joker80. 2. All of your material values for CRC pieces are unreliable since they are based upon and derived from #1 (corrupt statistical data). I hope you can handle constructive advice.
I am slightly relieved and surprised that Joker80 measurably improves the quality of its moves as a function of time or plies completed over a range of speed chess tournaments. Nonetheless, completing games of CRC (where a long, close, well-played game can require more than 80 moves per player) in 0:24 minutes - 36 minutes does NOT qualify as long or even, moderate time controls. In the case of your longest 36-minute games, with an example total of 160 moves, that allows just 13.5 seconds per move per player. In fact, that is an extremely short time by any serious standards. I consider 10 minutes per move a moderate time that produces results of marginal, unreliable quality and 60-90 minutes per move a long time that produces results of acceptable, reliable quality. Ask Reinhard Scharnagl or ET about the longest time per move they have used testing openings with their programs playing 'Unmentionable Chess'- 24 hours per move! It is noteworthy that you are now resorting to playing dirty by using the 'exclusivist argument' that essentially 'since I am not a computer chess programmer, I cannot possibly know what I am talking about when I dare criticize an important working of your Joker80 program'. What you fail to take into account is that I am a playtester with more experience than you at truly long time controls. If you will not listen to what I am trying to tell you, then why will you not listen to Scharnagl? After all, he is also a computer chess programmer with a lot of knowledge in important subject matters (such as mathematics). You really should not be laughing. This is a serious problem. Your sarcastic reaction does nothing to reassure my trust or confidence that you will competently investigate it, confirm it and fix it. Now, please do not misconstrue my remarks? My intent is not to overstate the problem. I realize Joker80 in its present form is not a totally random 'woodpusher'. It would not be able to win any short time control tournaments if that were the case. In fact, I believe you when you state that you have not experienced any problems with it but ... I think this is strictly because you have not done any truly long time control playtesting with it. You must decide upon and define the best primary function for your Joker80 program: 1. To pinpoint the single, very best move available from any position. [Ideally, repeats could produce an identical move.] OR 2. To produce a different move from any position upon most repeats. [At best, by randomly choosing amongst a short list of the best available moves.] These two objectives are mutually exclusive. It is impossible and self-contradictory for a program to somehow accomplish both. Virtually every AI game developer in the world except you chooses #1 as preferable to #2 by a long shot in terms of the move quality produced on average. If you do not even commit your AI program to TRYING to find the single best move available because you think variety is just a whole lot more interesting and fun, then it will be soft competition at truly long time controls facing other quality AI programs that are frequently-sometimes pinpointing the single, best move available and playing it against you.
'Joker80's strength increases with time as expected, in the range from 0.4 sec to 36 sec per move, in a regular and theoretically expected way.' 'The effect you mention is observed NOT to occur and thus cannot explain anything that was observed to occur.' Admittedly, I have no proof ... yet. Of course, this is due to Joker80 never have been playtested at truly long time controls (to my point of view). _______________________________________________________________ 'Now if you want to conjecture that this will all miraculously become very different at longer TC, you are welcome to test it and show us convincing results. I am not going to waste my computer time on such a wild and expensive goose chase.' I respect your bravery to issue the challenge. Although I would surely find the results of a randomized Joker80 vs. non-randomized Joker80 tournament at 60 minutes per move (on average) interesting, I am not willing either to invest a few (3-4) months of my computer time that I estimate it would require to playtest 16 games under acceptable, reliable conditions. My refusal is due to it not being extremely important or worthwhile to me just to keep the chess variant community from losing one potentially great talent to numerology (or some such). Besides, I have nothing to gain and nothing new to learn by conducting this long, difficult experiment. Only you stand to benefit tangibly from its results. I just cannot understand how any rational, intelligent man could believe that introducing chaos (i.e., randomness) is beneficial (instead of detrimental) to achieving a goal defined in terms of filtering-out disorder to pinpoint order. When you reduce the power of your algorithm in any way to filter-out inferior moves, you thereby reduce the average quality of the moves chosen and consequently, you reduce the playing strength of your program- esp. at long time controls. In other words, you are counteracting a portion of everything desirable that you achieve thru advanced pruning techniques used elsewhere within your program. Since you argue that randomization is no problem at all and I argue that randomization is a moderate-major problem, everything we say to one another is becoming purely argumentative. Only tests (that neither one of us intend to perform) can prove who is correct and settle the issue. ___________________________________________________________________ 'As I explained, it is very easy to switch this feature off. But you should be prepared for significant loss of strength if you do that.' To the contrary, you should be prepared for a significant gain of strength if you do that. Notably, you do not dare. In any event, the addition of the completely-unnecessary module of code used to create the randomization effect within Joker80 that you desire irrefutably makes your program larger, more complicated and slower. Can that be a good thing?
'It would be very educational then to get yourself acquainted with the current state of the art of Go programming ...' Go is a connection game that is not related to Chess or its variants. The only thing Go has in common with Chess is that it is played upon a board using pieces. You did not directly address my comment.
Rest assured, I intend to drop this futile topic of conversation soon and leave you alone. The following is my impression of how the limited randomization of move selection that you have described as being at work within Joker80 must be harmful to the quality of moves made (on average) at long time controls. Since you have experience and knowledge as the developer of Joker80, I will defer to you the prerogative to correct errors in my inferred, general understanding of its workings. _______________________________________________________ short time control 1x At an example time control of 10 seconds per move (average), Joker80 cuts thru 8 plies before it runs out of time and must produce a move. At the moment the time expires, it has selected 12 high-scoring moves as candidates out of a much larger number of legal moves available. Generally, all of them score closely together with a few of them even tied for the same score. So, when Joker80 randomly chooses one move out of this select list, it has probably not chosen a move (on average) that is beneath the quality of the best move it could have found (within those severe time constraints) by anything except a minor amount. In other words, the damage to playing strength via randomization of move selection is minimized under minimal time controls. ___________________________ long time control 360x At an example time control of 60 minutes per move (average), Joker80 cuts thru 14 plies (due to its sophisticated advance pruning techniques) before it runs out of time and must produce a move. At the moment the time expires, it has selected only 4 high-scoring moves as candidates out of a much larger number of legal moves available. Generally, all of them score far apart with a probable best move scored significantly higher than the probable second best move. So, when Joker80 randomly chooses one move out of this select list, the chances are 3/4 that it has ignored its probable best move. Furthermore, it may not have chosen the probable second best move, either. It just as likely could have chosen the probable third or fourth best move, instead. Ultimately, it has probably chosen a move (on average) that is beneath the quality of the best move it may have successfully found by a moderate-major amount. In other words, the damage to playing strength via randomization of move selection is maximized under maximal time controls. _______________________________________ The moral of the story is that randomization of move selection reduces the growth in playing strength that normally occurs with time and plies completed.
I have read that most computer chess programmers use the brute force method initially when the plies can be cut thru quickly and then switch to use advanced pruning techniques to focus the search from then on. This lead to my mis-interpretation that Joker80 would have more moves under consideration as the best at short time controls than long time controls. Some moves that score highly-positive after only a few-several plies will score lowly-positive, neutral or negative after more plies. Thus, I do not see how the number of moves under consideration as the best could prevent being reduced slightly with plies completed. As a practical concern, there is rarely any benefit in accepting the CPU load associated with, for example, checking a low-score positive move returned after 13-ply completion thru 14-ply completion (for example) when other high-score positive moves exist in sufficient number.
Upon reflection, I have no conceivable reason to be distrustful of using Joker80 IF I shut-off its limited randomization of move selection which Winboard F activates by default. Could you please give me example lines within the 'winboard.ini' file that would successfully do so? I need to make sure every character is correct.
Muller:
Thank you for the helpful response. Frankly, I considered my own question
so obvious as to be borderline-stupid but I just wanted to be certain.
The following entries within the 'winboard.ini' file should enable me to
playtest (limited) randomized and non-randomized versions of Joker80
against one another. Does it look alright? If/When I run out of more
pressing playtesting missions, I may undertake this one after all.
/firstChessProgramNames={'Joker80 22' /firstInitString='new\n'
'Joker80 22'
}
/secondChessProgramNames={'Joker80 22' /secondInitString='new\n'
'Joker80 22'
}
Unfortunately, I no longer plan to playtest sets of CRC piece values by
Muller, Scharnagl and Nalls against one another. I think having the pawn
set to 85 and the queen set to 950 (as required by Joker80) for all three sets of material values would have the unintentional side effect of equalizing their scales (which are normally different). This means that the Muller set would, in fact, be tested against something other than a true, accurate representation of the Scharnagl and Nalls sets.
I am currently in the midst of conducting several 'minimized asymmetrical
playtests' using SMIRF at moderate time controls. I want to tentatively
determine who is correct in disagreements between our models involving 2:1
or 1:2 exchanges (with supreme pieces). I have to avoid its checkmate bug,
though. This requires me to take back one move whenever the program
declares checkmate and 'call the game' if a sizeable material and/or
positional advantage indisputably exists for one player. Fortunately,
this is almost always the case. I will give a report in a few-several
weeks.'Of course you could also use Joker80 or TJchess10x8, which do not suffer from such problems.' ____________________ While you were on vacation, I started a series of 'minimized asymmetrical playtests' using SMIRF. So, I will complete them using SMIRF. Joker80, running under Winboard F, has never acted buggy in computer vs. computer games. However, TJChess cannot handle my favorite CRC opening setup, Embassy Chess, without issuing false 'illegal move' warnings and stopping the game.
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