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The xG of Chess: Shark Points

@BenjiPortheault said in #42:
> Hello testrider. Well if that was just this, then at the end of the game you would only get the final score as a value. The point is to map the 'maximum favorable excursion' point of the curve, hence, measure the point at which your chances of winning were maximal. Hope that helps to understand.

It might work well with high level play, where the variability is minimal along the game, but as others might have pointed out, maybe not here, often it is the last blunder that seals a game. Which would still allow for your definition to measure something, I am just wondering then about the chess-depth "time" scales. with many ups and downs and reversal even, in typical human games on lichess for example, one can still find a game maximum.. but it could be anywhere.

A more prudent GM game, where no little mistake goes unpunished, it might be easier.. Football, may not have that many forward backward movements. I have no clue , though.

There might actually be many such delayed conversions. So, given the model seems for high level games, I would assume that conversion means mater or something near end of game. The possibility that a game might have many opportunities of high potential score by engine, but human not converting as expected by engine in amplitude (and depth?), and missed conversions, would point to something one might integrate over whole game, but problem, choosing how to segment the game into high potentials, and conversions (amplitude and depth). The notion of potential versus immediate, is indeed an important question in chess. We often are very vague about the depths between "potential" and "immediate".

Also conversion in chess I have often seen in the context of positional advantage being converted into material count advantage some depth later. Was that what you meant from the football analogy? I guess if the rest of my post does not trigger any response, maybe just this question, might help me (to reduce my hesitations of understanding).

I think you are touching questions that need more thinking in chess, and trying to quantify it, is something I value. But, well, no but.
very interesting article! I love the metric xG in football and love to see that there is a comparable metric in chess. Just one question: Could the difference of shark points compared to the real points be seen as a weakness? Ding had more shark points than nepo, but didn't convert those. Isn't it more an indicium that Dings opponents made more mistakes and he therefore had more chances?