Author: Fernando Villegas
Date: 16:11:10 01/12/99
Go up one level in this thread
On January 11, 1999 at 23:03:24, STEPHEN A. BOAK wrote: >On January 11, 1999 at 21:40:52, Fernando Villegas wrote: > >>On January 10, 1999 at 23:11:10, Oliver Y. wrote: >> >>>On January 10, 1999 at 13:17:36, Fernando Villegas wrote: >>> >>>>On January 10, 1999 at 09:04:50, Oliver Y. wrote: >>>> >>>>>I have drawn a number of games against human masters, down a piece with little >>>>>or no compensation whatsoever. >>>>> >>>>>Earlier posts about true sacrifices might be related to this topic, and I >>>>>apologize in the unlikely event that I am duplicating an old discussion. >>>>> >>>>>I think current programs are particularly bad at having a chance at swindling to >>>>>save completely lost positions. >>>>> >>>>>If there's any interest, I can post two games where I was down a piece, >>>>> >>>>>a) I further sacked an exchange, so I'm down a rook; then I exchange my queen >>>>>for his 2 rooks and a knight..eventually I wind up with a mate in one using a >>>>>rook, bishop, and knight against his queen and bishop...which I miss in time >>>>>trouble. >>>>> >>>>>b) I sack another piece for some pressure, all along I am dead lost, so this >>>>>game score would be an embarrassment to the FIDE 2250+ master to post... >>>>>He blunders, and I have a won position, which I promptly turn into a perpetual >>>>>mate due to time pressure. >>>>> >>>>>Sorry, I guess I should just post the games already...but there's really no way >>>>>in the next 20 years you'll see programs finding effective swindles against >>>>>humans... >>>>> >>>>>That would be a true sign of Artificial Intelligence, IMMHO. >>>> >>>>Hi Oliver: >>>>I do not see an special extraordinary difficulty in that, at least in conceptual >>>>terms if not in practical one. Of course your expression "effective swindles" >>>>left open a door to rejects anything that is not defined as "effective", but >>>>thinking in swindles as such, the attitude to swindle, effective or not, in a >>>>practical game, I am not even sure some kind of swindling features were not >>>>present even in some very old programs. I remember Chess Champion by the >>>>Spracklen -1980- was willing to swindle -although clumsily-in lost positions and >>>>the same with his sucesor, Excellence and Par Excellence. I do not know for >>>>certain with current programs, but in fact, if that feature does not exist, what >>>>should be done -simplifying a lot- is not more than what we do in such >>>>circunstances. What we do? >>>>a) to detect that the opponent has an edge againts us, enough for a sure defeat >>>>in the long run and so understanding that "normal" playing has not sense >>>>anymore. >>>>b) Trying to transform the current form of disadvantage in another more complex >>>>form of disadvantage in order to get chances, even adding more abstract, >>>>material disadvantage for the sake of confusion and complexity. >>>>c) And as we do and as much as material disadvantage already exist, positional >>>>or justs attacking factors could overrun totally -or almost- material factors. >>>>In that way the engine could look for enterprising moves even if they are >>>>materially unsound in the very first ply of the search. >>>>fernando >>> >>>Hi Fernando, >>> >>>Excellent. A) is the key, and it should seem relatively simple to program. >>>This would seem the next logical extension of what Rebel was designed to do. >>> >>>B) and C) are much more difficult to do in DEAD LOST positions--I am at a loss >>>to even define the problem of how to mine for human patterns of weakness... >>> >>>Happy New Year... >> >>The same for you. And going again to the issue, have you seen how old programs, >>when lost, try to postpone the mate just pushing pieces to sacrifices, etc in >>order to stay alive one, two or three moves more? That's a kind of very >>primitive thinking-without-material-factor in the first place. I suppose you >>mean dead lost positions those where you are three pawns behind or the >>positional equivalent to that. I presume that, reached that limit, normal >>material and positional parameters should be replaced by something else. Again, >>we have something of the sort in the "combination" setting of many programs, >>where the engine is taught to search for sacrifices that could go after the >>enemy King, no matter how much the cost is. In fact, if you are dead lost, only >>direct attacks to the King have a sense. You can only search for mates. I am not >>a programmer, but I can imagine that that special module, kamisake kind, could >>be putted on each time that conditions of dead lost game was reached in order to >>search for sudden king attacks, no matter what. >>Fernando >>Fernando > >Fernando, > I disagree that if you are dead lost that only direct attacks to the King make >sense. > > Swindling, in a lost position, is the art of making moves that have traps. > > Suppose you are down a minor piece, and dead lost. You might play a move with >a subtle feature--that if your opponent does not spot the danger and exercise a >careful move in an otherwise winning position, you can trap a piece of his. >Maybe you could trap his queen, perhaps at the cost of only one additional minor >piece or rook; or maybe simply win back a minor piece. > > The trap doesn't have to result in mate, nor does it have to use the threat of >mate to work--although it could. It may simply allow a recovery of material. > > The art of swindling is in finding and setting traps that your opponent might >overlook, whether they mate, threaten mate, or simply win back material or even >defend with ingenuity (example--set up a drawing fortress in an otherwise losing >position where the fortress could have been prevented but was overlooked). >Voila! A swindle. > > Traps can be set by offering bait and luring your opponent, not just by >passive selection of moves with hidden threats. > >--Steve Hi steve: You are damm right. I oversimplified. Yes, you can swindle looking for traps as you have described so well and that's the way we swindle most of the time. Nevertheless, I hope my vision -including this time your traps- is not altoguether wrong, as much looking for traps is, in a way, to go out the traditional way the engine think. I mean, many times a trap can be very damaging for you IF the adversaryu does not fall in it, but you put it the same because you are already dead-lost. For doing that, the engine must desacrtivate his usual search technique based in maximal score, etc. Fernando
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