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I'll draw attention to the change I made today. Previously, when two players had ratings more than 400 points apart, GCR would calculate their provisional ratings by adding the lower rating to each player's percentage of games won times the full distance between them. Now, when two players have ratings more than 400 points apart, GCR calculates the midpoint between them, and calculates each player's provisional rating in a range between his current rating and 200 points past the midpoint. For example, if it compares two players at 1500 and 2000, the 1500 rated player's provisional rating would fall between 1500 and 1950, and the other's would fall between 1550 and 2000. The higher rated player's provisional rating is now calculated by subtracting the product of his opponent's score times the range. Since both scores add up to one, this is simply the same as using 1 minus his own score. The advantage of doing it this way is that the provisional scores for both players are only 400 points apart when the lower-rated player wins all games. Previously, this would give each player his opponent's rating as a provisional rating in this event, and that would be too much. After I made this change and fixed the bugs, the calculated ratings became slightly more accurate at predicting the original scores. So it seems to be an improvement.