How the ratings work
Each rating is a number for how well a team has played this season. It uses the Elo scale from chess, where 1500 is the league average and higher is better.
Everyone starts at 1500
Rosters change too much over a summer for last season to count. The games spread the teams out from there.
160015001400Timberwolves 1606Nets 1417Opening night, all at 1500
Every morning, every game again
Each morning every rating is worked out again from scratch, to best fit every result so far. So a win counts for more once the beaten team proves strong, and a team can rise on a day it doesn't play.
Thunder +4 on Sat, Oct 24, without playing
Tue, Oct 20 Thunder 116, Spurs 104 Sat, Oct 24 Spurs 122, Mavericks 106 Bigger wins count, less and less
A 43-point win counts only 3.4 times as much as a 1-point win, so a blowout padded in garbage time can't swing a rating. An upset or a bigger win earns more than a favorite's close win.
A bigger gap, a bigger favorite
Before tip-off, the gap between two ratings gives each team its chance to win. Home court is worth 64 points, measured over eight past seasons, so a home team is a 59% favorite over an equal rival.
Chance the higher-rated team wins
50%75%100%64 points, 59%0100200300400Rating gap, in points