What is Box Plus/Minus?
Box Plus/Minus (BPM) is a box score-based metric for evaluating basketball players' quality and contribution to the team. It is the latest version of a stat previously called Advanced Statistical Plus/Minus; it is NOT a version of Adjusted Plus/Minus, which is a play-by-play regression metric.
BPM relies on a player's box score information and the team's overall performance to estimate a player's performance relative to league average. BPM is a per-100-possession stat, the same scale as Adjusted Plus/Minus: 0.0 is league average, +5 means the player is 5 points better than an average player over 100 possessions (which is about All-NBA level), -2 is replacement level, and -5 is really bad.
To get a feel for the scale:
-The greatest seasons of all time by BPM are LeBron James' 2009 and 2010 seasons, and Michael Jordan's 1989 tour-de-force. All of those seasons had BPMs between +12.5 and +13.0.
-Some players who over their career were about average (+0.0) include Stephen Jackson, Kurt Thomas, Leandro Barbosa, James Donaldson, and Channing Frye.
The best player by BPM in 2013/14 was LeBron James, at +8.9, just above MVP Kevin Durant's +8.8. Kevin Love was close behind at +8.3, and Stephen Curry (+7.4) and Chris Paul (+7.4) round out the top five.
-Some players at or near +0.0 (average) from the 2013-14 NBA season include: Monta Ellis, Martell Webster, Iman Shumpert, Roy Hibbert, Nene Hilario, Ray Allen, Terrence Ross, and J.R. Smith.
-The worst player who played significant minutes in 2013-14 was Dennis Schroder of Atlanta, with a very poor -8.3 rating. Anthony Bennett, the surprise 2013 draft number 1 pick, followed with a -7.3