I can see how playing someone with a different rank above or below yours is treated (Victory/Loss vs weaker opponent, and Victory/Loss vs Stronger Opponent), but how is it dealt with when you play someone with the same ranking as yourself (Victory/Loss against Equal opponent)?
I noticed when I, at 16K, beat a 15K it was rated as a win over a weaker opponent, but when I as a 16K lost to a 17K it was rated as a loss to a weaker opponent. What is used to determine that? Shouldn’t my victory over the 15K be a win over a stronger opponent?
Note that it is currently not-at-all obvious which game is which with respect to those that count as against weaker and stronger opponents, because the graph only shows one update per day, incorporating the overall result of the day, and the game history doesn’t show the rank of the players at the time the game was played.
I’ve noticed this too, as a low 6 kyu I beat a high 5 kyu and it still counted as a weaker player. When I went back to see the rankings I noticed that with that most recent win I was a slightly higher rank than him, so I think the stronger weaker aspect is only evaluated after the rating change. Kinda weird, not sure if it’s intentional or not.