+/- and Defensive Charting Bonanza: Tennessee State, South Carolina, and UNLV

Caveat: Single-game +/- figures are so “noisy” (i.e., influenced by randomness) that they’re rendered practically useless. Even with a complete season’s worth of data, the +/- metric (especially in this– its unadjusted– form) suffers from this noisiness. Still, when taken in conjunction with the defensive box score, traditional box score, and old-fashioned “eye test,” the single-game +/- can be a part of the total evaluation process. It also serves as a good summary of Roy Williams’s substitution patterns/rotation.

Some definitions:

Pts-Pts All.: the points scored and points allowed by the team during a given player’s minutes
Off Eff: the points scored per 100 possessions with a given player on the court
Def Eff: the points allowed per 100 possessions with a given player on the court
Net Eff: the scoring margin per 100 possessions with a given player on the court

Since I’m dumping three games worth of data, I won’t provide many thoughts/explanations/trends/nuggets in this post. I’ve been posting a bunch of +/- and defensive charting tidbits on Twitter @FreeportKid, so definitely check that out if you’re interested in this kind of stuff. Once the schedule slows down a little (four games in one week is pretty intense), I’ll post a summary article discussing some +/- and defensive charting trends, analyses, and insights (especially some defensive stuff that relates to the UNLV loss, and some thoughts regarding Strickland/Bullock/Hairston and the allocation of minutes in the Carolina backcourt). Sorry this is essentially a pure data dump; I promise some analysis later (to provide some context and meaning to this sea of numbers).

Shifting gears, I’ve been charting every Carolina defensive possession since the 2004-05 season. This concept, aided by Luke Winn’s terrific Sports Illustrated piece, is finally getting some national attention. It’s a great way to measure individual defensive contributions and to see who’s making consistently timely and effective help-side rotations (the backbone of Roy Williams’s- and virtually any– defensive system). Click on the Winn link to read a little more about the charting process. (And here’s a piece by David Hess with even more on defensive charting.)

Some definitions:

FG-FGA: the made field goals and field goal attempts that a player is responsible for (both as a primary and help defender)– same for 3Pt-A and FT-FTA
Pts All.: the number of opponents’ points that a defender is responsible for allowing
TOF: forced turnovers (including offensive fouls drawn (OFD))
Defl.: deflections
DR (ORA): defensive rebounds and offensive rebounds allowed
Denies: when a player can deny an opponent or force an offensive reset by making a strong individual defensive play (of the type that doesn’t force a turnover or missed shot– i.e., wouldn’t otherwise show up in the defensive box score)

Tenn. State Shooting by Level of Contestedness:

• Open: 4-5 (0-1 3-pt.); 80.0 eFG%
• Lightly contested: 17-33 (10-21); 66.7 eFG%
• Contested: 7-24 (1-7); 31.3 eFG%
• Heavily contested: 0-9 (0-2); 0.0 eFG%

% of attempts well-contested: 46.5%

South Carolina Shooting by Level of Contestedness:

• Open: 4-5 (1-2 3-pt.); 90.0 eFG%
• Lightly contested: 19-29 (8-15); 79.3 eFG%
• Contested: 0-17 (0-6); 0.0 eFG%
• Heavily contested: 0-4 (0-0); 0.0 eFG%

% of attempts well-contested: 38.2%

UNLV Shooting by Level of Contestedness:

• Open: 8-9 (1-1 3-pt.); 94.4 eFG%
• Lightly contested: 19-38 (10-23); 63.2 eFG%
• Contested: 4-19 (2-8); 26.3 eFG%
• Heavily contested: 0-5 (0-0); 0.0 eFG%

% of attempts well-contested: 33.8%

Before presenting the cumulative +/- data through six games, a few more definitions:

Offensive On-Court/Off-Court: the difference in the team’s offensive efficiency during the possessions with a given player on the court and the possessions with that player on the bench

Defensive On-Court/Off-Court: the difference in the team’s defensive efficiency during the possessions with a given player on the court and the possessions with that player on the bench (presented such that a positive rating reflects that the team was better defensively with that player on the court, and a negative rating reflects that the team was worse defensively)

On-Court/Off-Court Rating: the difference in the team’s net efficiency during the possessions with a given player on the court and the possessions with that player on the bench; this is the metric by which players are ranked in the cumulative table that follows