Here are the NBA Betting Market (BTM) Power Rankings as of Thursday, January 19, 2012.
The general idea behind the rankings is to use the point spreads and over/unders for recent games (the past three weeks) to derive a power ranking, with more weight given to more recent games. There is also an adjustment that accounts for actual game outcomes. Refer to the Methodology page and my post at Advanced NFL Stats Community for more detail.
The big mover this week were the Dallas Mavericks, who moved from 11th to 5th (their GPF improving 1.5 points to 4.0). Key drivers of the movement were the line against the Lakers (four point underdogs on the road, which indicates the betting market felt those two teams were evenly matched, assuming a 3.5 point HCA) and a 2.5 point favorite over the Clippers on the road, indicating a 6 point gap between the two teams.
GlossaryHere is a glossary of terms used in the rankings table below (the structure of the table and the metrics shown draws significant inspiration from the Advanced NFL Stats Team Efficiency Rankings):
- lstwk - The BTM ranking from last week.
- GPF - Stands for "Generic Points Favored". It's what you would expect the team to be favored by against a league average opponent at a neutral site.
- GOU - Stands for "Generic Over/Under". It's what you would expect the betting over/under to be for the given team when playing a league average opponent (thanks to Jeff Fogle for the suggestion in last week's comments).
- oGPF - Stands for "Offensive Generic Points Favored". The component of a team's total GPF attributable to its ability to score points (per game).
- dGPF - Stands for "Defensive Generic Points Favored". The component of a team's total GPF attributable to its ability to prevent the other team from scoring points (per game).
- GWP - Stands for "Generic Win Probability". I converted the GPF into a win probability using the following formula: 1/(1 + exp(-GPF/6.5)).
- oRNK - The team's oGPF ranking.
- dRNK - The team's dGPF ranking.
The BTM Rankings:
Additional Key Factors:
- League Average Points Scored (APS): 95.0 points
- Home Court Advantage (HCA): 3.5 points
How to Use This Table to Build Point Spreads and Over/Unders
- Point Spread (in favor of home team) = HCA + (GPFhome - GPFaway)
- Over/Under = 2*APS + (oGPFhome + oGPFaway - dGPFhome - dGPFaway)