Finished games only. Each opponent counts once per game played, so a team met twice counts twice. Ties count as half a win. Regular-season games only.
Opponents' combined record adds up three parts: their record before playing the team, their record in the games against the team, and their record since.
Adjusted for opponents' schedules = (2 × opponents' winning percentage + opponents' opponents' winning percentage) ÷ 3, from finished games only. Each opponent's winning percentage leaves out its games against the team being ranked. Ties count as half a win.
Questions
Why does this differ from other strength-of-schedule rankings?
Many popular lists rate opponents by predicted power or point margin. Ours uses only real results: how often a team's opponents have won, plus how often those opponents' own opponents have won.