Advanced Stats Series: Part III

Rebound Percentages

The Story

Even the best team usually misses. And that means most of the time, there is an opportunity for a rebound, an opportunity for another chance.

In 2011-12, the Spurs led the NBA with a .478 Field Goal Percentage. In other words, even they missed the target 52.2 % of the time, excluding free throws. So basketball is not necessarily half offense and half defense. Some teams are stuck playing a lot more defense than offense, in part because they do not wrap up defensive rebounds. Theoretically, one team could play offense for an entire 12-minute quarter of basketball – if they kept missing and pulling in offensive rebounds.

Yet while we naturally think in terms of how often a player or team makes shots (think FG% and maybe even eFG%), most of us do not readily make that same type of connection when it comes to who gets the ball after the shot. But this is similarly important.

Enter Rebound Percentages.

The Stat

Think about it this way. The Spurs, as noted above, shot .478 from the field last season, while the Bobcats shot .414. That 6.4 % difference is major. And it is generally understood. But consider this: the Spurs led the NBA with a 76.0 Defensive Rebound Percentage, while the Bobcats lagged way behind at 70.9 %. That 5.1 % difference is also major, because it means that after an opponent shot went up, the Spurs gained possession much more often than the Bobcats.

Total Rebound Percentage is defined by basketball-reference as “an estimate of the percentage of available rebounds a player grabbed while he was on the floor.” This can be applied to teams, and can also be broken down to Offensive Rebound Percentage and Defensive Rebound Percentage – and that breakdown is worthwhile because many teams are very different when it comes to offensive and defensive rebounding.

The Examples

On the chart at the top, the teams highest up were the best ones at offensive rebounding. The teams furthest to the right were the best ones at defensive rebounding. Naturally, the optimal placement is the upper right corner, and conversely, the worst place to be is the lower left corner.

Spurs: The best offensive team in the NBA last season did not work wonders defensively, but they cleaned up the defensive glass better than any other team, the secret ingredient to their 50-16 regular season dominance.

Bulls: In their first matchup last season, the Bulls dropped the Bucks 107-100. In that game, the Bucks secured 29 defensive rebounds, while the Bulls pulled in 20 offensive rebounds – when the Bulls shot the ball and missed, they came back with the rebound 40.8 % of the time. The Bulls were the best offensive rebounding team in the NBA, and the best rebounding team overall.

Lakers: Balanced on both ends, the Lakers ranked sixth overall in offensive rebounding and fifth overall in defensive rebounding. While the departed Andrew Bynum was a top-flight rebounder, the team figures to dominate the glass even more this year after adding the best rebounder in the world, Dwight Howard.

Bobcats: The Bobcats were pretty dreadful rebounding on both ends of the court, compounding their myriad problems.

Celtics: The 2011-12 Celtics were the worst offensive rebounding team since the stat began being tracked in 1971, which raises questions. The consensus is that the team’s offensive (lots of jump-shooting big men) and defensive (prioritizing getting back on defense) philosophies played a large role in the historically low number Offensive Rebound Percentage, and that ineptitude was not necessarily the main factor.

Warriors: Adding Andrew Bogut to the lineup should help shore up the team’s glaring, foremost weakness from last season: defensive rebounding.

The Bucks

One of the most memorable plays of last season was Ersan Ilyasova’s game-winning tip-in against the Wizards. Indeed, Ilyasova vaulted into elite territory with a 12.7 Offensive Rebound Percentage, by far the best mark of his career. And he was chiefly responsible for the team finishing with a very respectable 13th overall in Offensive Rebound Percentage.

However, defensive rebounding proved to be a major problem, as the Bucks ranked 25th overall. Ilyasova (22.8) was the best of the bunch, but without a traditional, natural center on the active roster for much of the season, the team collectively struggled to bring in defensive rebounds. And it hurt. The problem manifested early, when the Kings dealt the Bucks a loss in the eighth game of the season after winning the rebounding battle 55-31, and it continued throughout the season.

The Outlook

Samuel Dalembert is not just large. I mean, he is that, too. But when you hear people talking about how he is a real center, there is actually some credence to those lines. First of all, Dalembert is an exceptional rebounder. In fact, he is in the top ten in NBA history in Total Rebound Percentage. His best rebounding season was 2009-10, but he remained near the league leaders as of last season. He should help on the boards, all over the boards, immediately and immensely this season.

New backup center Joel Przybilla is historically a very good rebounder as well, even having led the NBA in Defensive Rebound Percentage and Total Rebound Percentage in 2008-09. His numbers have dipped some since then, but rebounding remains the strength of his game.

Ilyasova is a growing force on the glass, and the rest of the frontcourt stable is competent on the boards as well. Drew Gooden typically rebounds well for a power forward, rookie John Henson was a superb rebounder in college, and while Ekpe Udoh did not post big rebounding numbers in Golden State, he improved quite a bit after arriving in Milwaukee.

On paper, on a computer screen, on a cell phone – wherever you look right now, the Bucks are an improved rebounding team. And after missing out on so many boards in a down year last season, they have an opportunity on the court to rebound this season. 

Alex Boeder

My passions? Writing and the Bucks, to start. So it is good to be here. I have reported on media row for just about every Bucks home game since 2009-10 – almost all of that time writing for BrewHoop. I have also written for the Milwaukee Brewers Baseball Club, SB Nation, ESPN Milwaukee, Slam Online, etc. You can follow me on Twitter @alexboeder or email me at adboeder@gmail.com.