Author: Sune Fischer
Date: 10:01:26 07/31/04
Go up one level in this thread
On July 31, 2004 at 10:43:44, Robert Hyatt wrote: >OK. That can be measured. I search with a very narrow aspiration window. I >don't believe a null-window will fail low 5% faster, but I'll run that test >tonight to find out and post the numbers... I think it would, what else is the point of nullwindows in general? It gives you very little information (never an exact score), so if it's not faster... >>>We are _always_ testing A+B+C+D+E+F against G+H+I+J+K+F. Because the searches >>>are different, the extensions are different, the evals are different, etc. >> >>I think this smokescreen isn't worth the paper it isn't written on. >> >>I suppose it is not possible for you to test PVS and nullmove as it has been >>described either? > > >Those are _your_ words, not mine. Remember? You complained that my null-window >search wasn't done the same way you suggested because something _else_ in my >search was different. No I said something else in your _experiment_ was different. If you make several changes in the same experiment, then it's not easy to say which is causing what. Maybe you threw out the baby with the bathwater. > I just pointed out that _lots_ of things in my search are >different, Of course, and your point would be...? > so using your logic, we can't compare _anything_. Before you start analysing my logic it would be nice if you could understand what I'm talking about. >I agree the idea is broken. But it wasn't _my_ idea. :) So you make your conclusions _before_ you run the experiment? Fasinating, and how incredibly errorprone. >>I don't believe this can practicly happen if you use careful estimates. > >I know it _does_ happen. I am looking at log files all the time and see some >very unusual timing issues that are surprising... Well, maybe it won't work in Crafty then. I'm sure you'll come to that conclusion regardless with your very objective way of concluding things. >>Ok, so your don't want to do anymore hassle on this part of your program. >>It is perfect as it is! ;) > > >"Perfect as it is" is your term. "better as it is" is my term. Ah, so you admit there is room for improvement! That in itself is an improvement I think :) >>I'm just not ready quite yet to throw in the towl. >> >>>>Starting off by a careful estimate, eg. 20%, should be safe and good enough to >>>>assert if it works or not. >>> >>> >>>Where does 20% come from? v=rand()*100 or something similar? >> >>Experience, from watching a lot of engine output. >> >>I can not remember _ever_ having seen Time(ply N+1) < 0.20*Time(ply n) > > >I posted one such example already. Another way to see odd results is a deep >ponder search on the wrong move, where the hash table then provides scores that >make search times way beyond unpredictable due to transpositions between the >move pondered and the move played. I repeat: I have _never_ seen such a position. you posted this, as an example of an extreme position: >> 35-> 15.93 8.92 1. Kb1 Kb7 2. Kc1 Kb8 3. Kc2 Kb7 4. >> Kc3 Kc7 5. Kd3 Kb7 6. Ke2 Kc7 7. Kf3 >> Kd7 8. Kg3 Ke7 9. Kh4 Kf6 10. Kh5 Kf7 >> 11. Kg5 Kg7 12. Kxf5 Kf7 13. Ke4 Ke8 >> 14. Kd3 Ke7 15. Kc4 <HT> >> 36 17.33 8.92 1. Kb1 Kb7 2. Kc1 Kb8 3. Kc2 Kb7 4. >> Kc3 Kc7 5. Kd3 Kb7 6. Ke2 Kc7 7. Kf3 >> Kd7 8. Kg3 Ke7 9. Kh4 Kf6 10. Kh5 Kf7 >> 11. Kg5 Kg7 12. Kxf5 Kf7 13. Ke4 <HT> >> 36-> 17.33 8.92 1. Kb1 Kb7 2. Kc1 Kb8 3. Kc2 Kb7 4. >> Kc3 Kc7 5. Kd3 Kb7 6. Ke2 Kc7 7. Kf3 >> Kd7 8. Kg3 Ke7 9. Kh4 Kf6 10. Kh5 Kf7 >> 11. Kg5 Kg7 12. Kxf5 Kf7 13. Ke4 <HT> >> 37 18.68 8.92 1. Kb1 Kb7 2. Kc1 Kb8 3. Kc2 Kb7 4. >> Kc3 Kc7 5. Kd3 Kb7 6. Ke2 Kc7 7. Kf3 >> Kd7 8. Kg3 Ke7 9. Kh4 Kf6 10. Kh5 Kf7 >> 11. Kg5 Kg7 12. Kxf5 Kf7 13. Ke4 <HT> >> 37-> 18.70 8.92 1. Kb1 Kb7 2. Kc1 Kb8 3. Kc2 Kb7 4. >> Kc3 Kc7 5. Kd3 Kb7 6. Ke2 Kc7 7. Kf3 >> Kd7 8. Kg3 Ke7 9. Kh4 Kf6 10. Kh5 Kf7 >> 11. Kg5 Kg7 12. Kxf5 Kf7 13. Ke4 <HT> a = time(ply 36) = 17.33-15.93 = 1.40 b = time(ply 37) = 18.70-17.33 = 1.37 So we have b = 0.986*a. I don't where you took math, but I was tought that 0.986 is MUCH LARGER than 0.20. Correct me if I'm wrong. -S.
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