NBA

# The Correlation Between Team Stats and Offensive and Defensive Efficiency, Part 4: Rebounds

So far, we've looked at steals, blocks, and turnovers, and how they relate to offensive and defensive efficiency. What about rebounds?

Today weâ€™re continuing our series of looking at pace-adjusted team stats in relation to team offensive and defensive efficiency. There are six parts of this series; weâ€™ve already done steals, blocks, and turnovers (both live and dead-ball), and this article will be devoted to exploring rebounds.

As a reminder, I've plotted out each teamâ€™s offensive and defensive rating in relation to their total team rebounds, going back 10 years. I then set a trendline, which will let us see the correlation, or lack thereof. In the equation, the number next to â€œxâ€ will tell us the exact numerical correlation between the team stat and offensive or defensive efficiency. Lastly, our coefficient of determination (RÂ²) will tell us whether our correlation is meaningful.

Letâ€™s talk rebounds.

### How Rebounds Affect Team Offenses

Over the past two years, it looks like there has been zero correlation between team rebounding and offensive efficiency. Our equation technically says there is a negative correlation, but since the RÂ² value is zero, we can deduce that there has in fact been no relation between these two statistics.

When we expand the data to include the past 10 years, the correlation becomes positive, although it is still a slight one at best. Looking at our RÂ² value again, we can see that, while not zero, itâ€™s still way too small to conclude that there is any correlation to be found.

Why could this be? It seems intuitive that good defensive rebounding teams would potentially have more transition opportunities â€“ a run-out after a long, missed three-pointer, for example. And offensive boards clearly have a strong correlation to offensive efficiency, as those generally lead to high-efficient shots â€“ dunks and layups.

Perhaps the correlation between transition opportunities and defensive rebounding itself isnâ€™t quite as strong as we would intuitively think. And while offensive rebounds help, they are a small percentage of a teamâ€™s total rebounds in relation to defensive boards. For example, the Golden State Warriors grabbed the fifth-most boards in the league last year. However, offensive boards only accounted for 896 of their total 2819 rebounds, or 31.8%.

### How Rebounds Affect Team Defenses

The two-year data shows that there is quite an obvious trend between rebounding and defensive efficiency. In the past two years, a rebound has lowered a teamâ€™s defensive rating (points allowed per 100 possessions) by 0.71 points, on average. That is significant.

However, itâ€™s not as significant as the trend we find when we expand the data to include the past 10 years. In the past 10 years, a team has saved a full point per 100 possessions for each team rebound grabbed. The RÂ² value of 0.295 is the highest weâ€™ve seen and implies that we can find this correlation meaningful.

Looking at last yearâ€™s best rebounding teams, almost all of the top defensive squads were above-average rebounding teams as well â€“ the Warriors, Spurs, Clippers, Bulls, and Pacers were all in the upper half of the league.