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I've been more closely comparing different approaches to the ratings. One is the new approach I described at length earlier, and one is tweaking the stability value. In tweaking the stability value, I could increase the accuracy measurement by raising the number of past games required for a high stability score. But this came at a cost. I noticed that some players who had played only a few games quickly got high ratings. Perhaps they had played a few games against high rated players and won them all. Still, this seemed to be unfair. Maybe the rating really was reflective of their playing abilities, but it's hard to be sure about this, and their high ratings for only a few games seemed unearned. In contrast to this, the new rating method put a stop to this. It made high ratings something to be earned through playing many games. Its highest rated players were all people who had played several games. Its highest rating for someone who played games in the single digits was 1621 for someone who had won 8.5 out of 9 games. In contrast, the tweaked system gave 1824 to someone who won 4 out of 4 games, placing him 5th in the overall rankings. The current system, which has been in place for years, gave 1696 and 1679 to people who won 8.5/9 and 4/4 respectively.

In the ratings for all games, the new system gets a lower accuracy score by less than 2%. That's not much of a difference. In Chess, it gets the higher accuracy score. In some other games, it gets a lower score by a few percentage points. Generally, it's close enough but has the advantage of reducing unearned high ratings, which gives it a greater appearance of fairness. So I may switch over to it soon.