Author: Robert Hyatt
Date: 14:05:07 02/04/03
Go up one level in this thread
On February 04, 2003 at 15:29:00, Jarkko Pesonen wrote: >The position was derived from this earlier position. >There is 9th move Nc3 > >[D] 7r/2qpkp2/p3p3/6P1/1p5r/7P/PPP2QK1/R2N1R2 b > >Crafty 19.3 > > 7 0.12 1.93 2. ... Qc6+ 3. Qf3 Rxh3 4. Qxc6 dxc6 > 5. Nf2 Rh2+ 6. Kf3 Re8 > 7-> 0.25 1.93 2. ... Qc6+ 3. Qf3 Rxh3 4. Qxc6 dxc6 > 5. Nf2 Rh2+ 6. Kf3 Re8 > 8 0.36 1.81 2. ... Qc6+ 3. Qf3 Rxh3 4. Qxc6 dxc6 > 5. Rf4 Rh2+ 6. Kf1 Rg8 7. Ne3 Rxg5 > 8. Rxb4 > 8-> 0.89 1.81 2. ... Qc6+ 3. Qf3 Rxh3 4. Qxc6 dxc6 > 5. Rf4 Rh2+ 6. Kf1 Rg8 7. Ne3 Rxg5 > 8. Rxb4 > 9 1.04 1.47 2. ... Qc6+ 3. Qf3 Rxh3 4. Qxc6 dxc6 > 5. Nf2 R3h5 6. Kf3 Rxg5 7. Rad1 > 9 5.67 ++ 2. ... Rxh3!! > 9 8.11 0.79 2. ... Rxh3 3. Qxf7+ Kd8 4. Qf6+ Ke8 > 5. Kf2 Qxc2+ 6. Ke1 Qe4+ 7. Kd2 Qd3+ > 8. Kc1 Qc4+ 9. Nc3 bxc3 > 9-> 8.76 0.79 2. ... Rxh3 3. Qxf7+ Kd8 4. Qf6+ Ke8 > 5. Kf2 Qxc2+ 6. Ke1 Qe4+ 7. Kd2 Qd3+ > 8. Kc1 Qc4+ 9. Nc3 bxc3 > 10 10.73 1.00 2. ... Rxh3 3. Qxf7+ Kd8 4. Qf6+ Ke8 > 5. Kf2 Qxc2+ 6. Ke1 Qe4+ 7. Kd2 Qd3+ > 8. Kc1 Qc4+ 9. Nc3 bxc3 10. g6 cxb2+ > 11. Kxb2 > 10-> 17.01 1.00 2. ... Rxh3 3. Qxf7+ Kd8 4. Qf6+ Ke8 > 5. Kf2 Qxc2+ 6. Ke1 Qe4+ 7. Kd2 Qd3+ > 8. Kc1 Qc4+ 9. Nc3 bxc3 10. g6 cxb2+ > 11. Kxb2 > 11 23.64 ++ 2. ... Rxh3!! > 11 34.36 0.56 2. ... Rxh3 3. Qxf7+ Kd8 4. Qf6+ Ke8 > 5. Kf2 Qxc2+ 6. Ke1 Qe4+ 7. Kd2 Qd3+ > 8. Kc1 Qc4+ 9. Nc3 bxc3 10. g6 cxb2+ > 11. Kxb2 Rh2+ 12. Ka3 > 11-> 42.58 0.56 2. ... Rxh3 3. Qxf7+ Kd8 4. Qf6+ Ke8 > 5. Kf2 Qxc2+ 6. Ke1 Qe4+ 7. Kd2 Qd3+ > 8. Kc1 Qc4+ 9. Nc3 bxc3 10. g6 cxb2+ > 11. Kxb2 Rh2+ 12. Ka3 > 12 1:18 ++ 2. ... Rxh3!! > 12 3:11 0.00 2. ... Rxh3 3. Qxf7+ Kd8 4. Qf6+ Ke8 > 5. Kf2 Qxc2+ 6. Ke1 Qe4+ 7. Kd2 Qd3+ > 8. Ke1 Re3+ 9. Nxe3 Qxe3+ 10. Kd1 Qd3+ > 11. Ke1 Qe3+ > > >Ruffian: > Depth Time Score Best line > 8/23 1.51 ++ ... f5 > 8/23 2.53 -1.21 ... f5 Rg1 Rxh3 Qd4 Qxc2+ Kf1 Ke8 Ke1 a5 > 8--> 2.73 -1.21 ... f5 Rg1 Rxh3 Qd4 Qxc2+ Kf1 Ke8 Ke1 a5 > 9/24 3.76 -1.31 ... f5 Rg1 Rxh3 Kf1 Rh2 Qd4 Qxc2 Qxb4+ Ke8 Qb8+ Ke7 > Qe5 > 9/25 5.42 x.xx ... Rxh3 > 9/25 5.95 ++ ... Rxh3 > 9/26 7.06 0.00 ... Rxh3 Qxf7+ Kd8 Qf6+ Ke8 Kf2 Qxc2+ Ke1 Qe4+ Kd2 > Qd3+ Kc1 Qc4+ Kb1 Qe4+ Kc1 Qc4+ > 9--> 7.53 0.00 ... Rxh3 Qxf7+ Kd8 Qf6+ Ke8 Kf2 Qxc2+ Ke1 Qe4+ Kd2 > Qd3+ Kc1 Qc4+ Kb1 Qe4+ Kc1 Qc4+ > 10/28 8.92 0.00 ... Rxh3 Qxf7+ Kd8 Qf6+ Ke8 Kf2 Qxc2+ Ke1 Qe4+ Kd2 > Qd3+ Kc1 Qc4+ Kb1 Qe4+ Kc1 Qc4+ > 10--> 9.87 0.00 ... Rxh3 Qxf7+ Kd8 Qf6+ Ke8 Kf2 Qxc2+ Ke1 Qe4+ Kd2 > Qd3+ Kc1 Qc4+ Kb1 Qe4+ Kc1 Qc4+ > 11/31 14.73 0.00 ... Rxh3 Qxf7+ Kd8 Qf6+ Ke8 Kf2 Qxc2+ Ke1 Qe4+ Kd2 > Qd3+ Kc1 Qc4+ Kb1 Qe4+ Kc1 Qc4+ > 11--> 17.62 0.00 ... Rxh3 Qxf7+ Kd8 Qf6+ Ke8 Kf2 Qxc2+ Ke1 Qe4+ Kd2 > Qd3+ Kc1 Qc4+ Kb1 Qe4+ Kc1 Qc4+ > > >There is difference in speed an in which ply depth >draw is detected > >Jarkko Ruffian is obviously extending more than I am. I happen to not want to waste a lot of time following deep checking sequences that lead to nothing, so I limit the checks in the hope of finding a deeper positional move instead. It's a matter of taste... > >****************************************** > >On February 04, 2003 at 13:28:55, Robert Hyatt wrote: > >>On February 04, 2003 at 13:26:43, Robert Hyatt wrote: >> >>>On February 04, 2003 at 08:37:57, Jarkko Pesonen wrote: >>> >>>>[D] 4k2r/3p4/p3pQ2/6P1/1pq5/7r/PP6/R1KN1R2 w >>>> >>>>This is draw , but how do you statically can evaluate that it so? >>>> >>>>This was the quiescent position and crafty suggested Nc3 bxc3 and not go for >>>>repetion(eval 0.09 for crafty statically after these moves but search from this >>>>position reveals that this loses rook at lest ) and ruffian correctly wanted to >>>>play Kb1 which was the repeating move. >>>> >>>> >>>>Anyway ruffian seems to find drawing lines much sooner than crafty. >>>>Does anyone have a glue why it is so fast. >>>>It catches draw a few ply earlier than crafty. >>>>Is there a way fix this in crafty? >>>> >>>> >>>>Jarkko >>> >>> >>>You are probably mis-interpreting the concept of "draw". >>> >>>For a program to see a draw by repetition, two things have to happen: >>> >>>1. It has to believe that one side can _force_ the repetition, if the other >>>side plays >>>in a particular way. >>> >>>2. It has to believe that the other side would be worse off it it tries to >>>avoid the >>>repetition. >>> >>>All you need in a position like this is to think that one side is is better than >>>the other, >>>and you might or might not be able to see the repetition. IF one program thinks >>>white is slightly better, then it would think that black would try to force the >>>repetition >>>and white must go along or else get "worse". If another program thinks black is >>>better, then it might totally ignore the repetition opportunity. >>> >>>Usually one side has the option to vary, say in a perpetual check the checking >>>side doesn't >>>have to check. But he has to believe that if he doesn't check, the opponent has >>>a better >>>resulting position. If that is not true, the perpetual won't be played. >> >> >>I tried this position and Crafty spots a repetition instantly: >> >> 5 0.04 -Mat04 1. Kd2 Rd3+ 2. Ke1 Qe4+ 3. Kf2 Rh2+ >> 4. Kg1 Qh1# >> 5 0.07 -0.46 1. Nc3 bxc3 2. g6 cxb2+ 3. Kxb2 d6 >> 5 0.07 0.00 1. Kb1 Qd3+ 2. Kc1 Qc4+ >> 7 0.15 0.00 1. Kb1 Qd3+ 2. Kc1 Qc4+ >> 7-> 0.16 0.00 1. Kb1 Qd3+ 2. Kc1 Qc4+ >> 8 0.33 0.00 1. Kb1 Qd3+ 2. Kc1 Qc4+ >> 8-> 0.42 0.00 1. Kb1 Qd3+ 2. Kc1 Qc4+ (s=2) >> 9 0.93 0.00 1. Kb1 Qd3+ 2. Kc1 Qc4+ >> 9-> 1.01 0.00 1. Kb1 Qd3+ 2. Kc1 Qc4+ >> 10 2.34 0.00 1. Kb1 Qd3+ 2. Kc1 Qc4+ >> 10-> 2.38 0.00 1. Kb1 Qd3+ 2. Kc1 Qc4+ >> 11 7.25 0.00 1. Kb1 Qd3+ 2. Kc1 Qc4+ >> 11-> 7.68 0.00 1. Kb1 Qd3+ 2. Kc1 Qc4+ >> 12 29.98 0.00 1. Kb1 Qd3+ 2. Kc1 Qc4+ >> 12-> 30.48 0.00 1. Kb1 Qd3+ 2. Kc1 Qc4+ >> >> >>I'm not sure it could do any better than .07 seconds for spotting this, and this >>was not >>run on my dual xeon either, but on a quad 550 that is about 1/3 the speed...
This page took 0 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.