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Ovyron wrote: ↑Sat Sep 07, 2019 9:14 pm

lkaufman wrote: ↑Thu Sep 05, 2019 6:11 pm With SF it is the basic definition of what score to return when a clean pawn ahead on a full board that has changed many times. I usually use the opening position with f2 removed to measure this

I really don't think that works in practice for actual chess positions. I have full records of actual chess positions (usually openings) that I've analyzed over the years since 2007, with Glaurung and Stockfish versions more and more modern included, where it's clear the trend has been getting a score closer to 0.00 - positions where old Stockfish used to say "0.80" and today's Stockfish says "0.19". And I hadn't seen a jump in recent years in the scale.

If anything, over the years Stockfish's eval and the material on the board has become disjointed, 1.00 as an advantage has not meant "a pawn advantage" for a long while now, and I don't even know what it means anymore. All I know is that, all things being equal, you'd rather have that 1.00 advantage than a 0.90 advantage, and it usually correlates with chances of winning, specially against weak opposition.

lkaufman wrote: ↑Thu Sep 05, 2019 6:11 pm I certainly don't think that a 0.1 change has no significance, just that it is small enough to allow a strongly held belief by a 2800 player that the second move is better to overrule it.

I'd agree, specially if the 0.1 better move is trading a very important piece that may be key to winning, or break a pawn structure that one just knows is worse than the alternative, etc. My question is, how many of such overrules are you going to allow per game, and then, why are the overrules closer to the limit more significant than the others? (say, if you allow 5 such overrules, once you have burned out 4, the last one is significant because it means you can't do another in the game.)

My claim is overruling depends on the advantage or disadvantage that you already have on the game, so a "0.1" score difference can't be applied to all situations. A difference between 0.90 and 1.00 disadvantage might be the difference between saving and losing the game, while a difference between 0.00 and 0.10 might be the difference between increasing your chances of winning or giving the opponent an easy draw. Both are significant scenarios at the edge, and there's no point I can discern where a difference of this magnitude is insignificant.

lkaufman wrote: ↑Sun Sep 08, 2019 1:21 am A 0.1 difference is always enough to take seriously. I think the question is, if we are playing a correspondence game (if it's OTB we won't know the engine eval without cheating), we can consider lots of evidence.

lkaufman wrote: ↑Sun Sep 08, 2019 1:21 am A 0.1 difference is always enough to take seriously. I think the question is, if we are playing a correspondence game (if it's OTB we won't know the engine eval without cheating), we can consider lots of evidence. The eval from multiple engines, the stats from database if it's a known position, and the opinion of the player if the player is strong enough for this to be relevant. Also the result of interactive analysis. The number of previous "overrules" is irrelevant, just like knowing the history of dice throws is irrelevant to predicting the next one. The absolute score may have something to do with the decision, but there's no obvious rule about this. I'm just saying that if the score diff is 0.2, especially if not contradicted by another strong engine, then you probably shouldn't waste much time on the decision, but if it is 0.1, it is probably worthwhile to look further if you are a very strong player or at least very skilled in interactive analysis.