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The thing about all those games, is that there were two active participants that each had opportunity.
Pool isn't always like that.
In rotation pool, you have situations where only one player is at the table for a game won, when they break and run out. How is it fair to take away points from the loser of that game if they were never at the table?
Is it really fair to give that game the same value as a game where both players were at the table and had opportunities to win?[...]
What you are addressing is what we refer to as the run-length issue. Effectively, when an inning between two players spans more than a scoring unit, the information content in the score is reduced. This is not a problem, but it is something to be understood and addressed.
Imagine two very weak players playing straight pool. Though one player is 100 points better than the other, they are both sufficiently weak that neither is likely to make two balls in one turn at the table. Mostly they bat a ball around until somebody makes it for each point.
For these two, a single race to 10 in straight pool is sufficient to establish who is the better player. The information content in the score is pretty high.
If the match was played six times, the scores might be
10-5
10-4
10-5
10-6
10-4
10-6
For SVB and a low-level pro (also 100 points apart), a single race to 10 in straight pool contains almost no information. If that match is played six times the scores might be
10-0
10-2
8-10
2-10
10-0
10-6
I use straight pool because it is an extreme example. For rating players playing rotation games, this is relevant in two ways. First because innings (skill-induced changes in control) span games (whether with winner breaks or with alternate breaks) the information content in the score is reduced. This is not itself a big deal. It just means more total games are required to establish a reliable rating.
Where it matters, though, is comparing different games:
Suppose PRO1 beats PRO2 11-6 playing 9-ball on a 7-foot table today,
and then PRO2 beats PRO1 tomorrow 11-6 playing 10-ball on a 9' table.
We intuitively see more "information" in the 10-ball on a 9' table score. That is, if we had to guess from this overall 17-17 score who is the better player, most of us would put our money on PRO2.
This distinction is real. And it can be incorporated using information theory and run-length (break & run) statistics. Essentially a race to 7 on a 9' table can for example be given the equivalent weight of a race to 9 on a 7' table.
Be aware, though, that for weaker players, this distinction goes away.