Data Digging: Plus/Minus revealing for Duke basketball

After a loss it is reasonable for fans to be calling for lineup changes. After all, Mike Krzyzewski changed his own lineup after a close call at Wake Forest last week, replacing Amile Jefferson with Matt Jones for Sunday's loss against the Wolfpack.

But before you lose your voice screaming for some roster reshuffling, let's take a look at some numbers.

Plus/Minus isn't the best stat in the world, but it can be a useful one. Especially when compared to the team's Plus/Minus when a player is on the bench. By taking the difference between the team's Plus/Minus with a player on the floor and with him on the bench, you get a reading of many net points are gained or lost with a specific player on the court.

Of course, this stat is marred by who each player is playing with when on the court. Marshall Plumlee doesn't get the benefit of playing next to Jahlil Okafor and so his adjusted Plus/Minus will take a hit. But let's ignore the limitations for a minute and take a look at the numbers.

As you may have guessed from watching any Duke basketball this season, the Blue Devils' top two contributors have been Quinn Cook and Okafor. Duke is on average 11.53 points per game better with Cook on the court and 10.2 points better with Big Jah manning the middle. Tyus Jones and Justise Winslow also grade out positively at 7.53 and 6.2 apiece. Somewhat more surprisingly, the oft-unnoticed Matt Jones also receives a positive grade thanks to his strong games in ACC play.

Junior Amile Jefferson is the only Blue Devil starter with a negative Plus/Minus rating.

A notable missing name from the above list is that of Amile Jefferson. Times have been tough for the Philadelphia native, as Duke has been doing 17.8 points per game worse with Jefferson than without him in the past five games. That just so happens to correspond exactly with Matt Jones' stretch of five games with a +9.0 rating. I think we're starting to see why it was DeSoto's finest who earned the start against N.C. State. And despite the poor result, Duke was outscored by only four points with Jones on the floor, versus eight points with him riding the pine for 20 minutes, making Jones one of just three Blue Devils to register a positive grade that game.

To have more success as the season wears on, the Blue Devils will need to get more from their top guns in games against better opponents.

Captain Cook's mark of 11.53 leads the team, but in games against teams rated in Ken Pomeroy's top 100—Michigan State, Temple, Stanford, Wisconsin, Toledo, Connecticut and N.C. State—that number falls all the way to 8.0. The slack has been picked up by Tyus Jones and Justise Winslow, who seem to have a flair for the dramatic by performing well in big games. Both freshmen have point differentials better than 11.4 against those seven opponents. Winslow's 11.43 mark is particularly impressive considering Chief Justise's disappointing -6 against Wisconsin.

It is widely accepted that conference play is a whole different animal in college basketball. Although sample size may come into play, that has held true for the Blue Devils. I've already touched on Matt Jones' prodigious play of late, and he has predictably been joined by Captain Cook and Chief Justise at the top of Duke's leaderboard. But the positive surprise of conference season has been Rasheed Sulaimon, who has a +6.33 mark in three ACC games compared to his -4.73 mark on the season. After an inauspicious start, Duke has had a serious need for 'Sheed against Boston College and N.C. State. The Blue Devils outscored the Eagles by 19 with Sulaimon on the hardwood, and played the Wolfpack to a draw in his 22 minutes of action.

As for a negative surprise, look no further than Duke's leading scorer—Jahlil Okafor. The freshman actually has Duke's best mark at 12.57 in games against KenPom's top 100, but has a -2.33 rating in conference play. Okafor may have had some pretty counting stats against N.C. State with 23 points and 12 boards, but only Jefferson and Tyus Jones faired worse in the adjusted Plus/Minus department. Duke didn't lose any ground on N.C. State while Okafor sat.

Tyus Jones has actually been worse than Okafor in conference play, grading out negatively in both the Boston College and N.C. State games. In fact, in the 13 minutes Duke played against the 'Pack without Jones, the Blue Devils gained five points.

Now that I've laid out the numbers for you, let's take a moment before demanding changes. This stat isn't the end all and be all of production, but it is worth monitoring moving forward. Only time will tell if Okafor and Jones perk up as conference play wears on; if Matt Jones and Sulaimon continue to be key contributors; if Jefferson can rediscover his mojo. For now, let's put the breaks on panic over one loss and look forward to the rest of what remains a very promising season.


Share and discuss “Data Digging: Plus/Minus revealing for Duke basketball” on social media.