Dean Oliver is a genius
If you watched the Thunder/Bulls game the other night, especially somewhere in the second half, you might have had the same reaction that I and many other commenters here at DT had: how in the heck can we have a lead when we can’t get a rebound?”
Royce noticed it and made note in the recap, others suggested similar sentiments in the comments. I didn’t so much put the two together but just felt like we were getting crushed on the boards and hoped we didn’t give our lead away. The basketball gods smiled on us and we were able to put Chicago away despite a 25-13 deficit in offensive rebounds.
Offensive rebounds are flashy. They are like a 3-point shot in that they make you cheer in close games when your team gets one or makes one. If you are on the other side of the equation they feel like a gut punch. Your team is busy playing tough defense and they force the opponent into a tough shot that they miss only to see their freaking point guard come up with the Oreb and reset the offense with a fresh 24. It’s painful to watch and it makes you scream at your Center and Power Forward “why didn’t you box out“? Invariably after a few of those games or sequences us fans on the board begin to work out trade scenarios whereby we can ship off our inept bigs for guys that actually do box out and get the boards.
Rebounds are important. No doubt about it and I don’t want to diminish them. And the more we get the more we increase our chances of winning, but just HOW important are they?
A good maxim in life is that if you don’t know something, look it up. Consult an expert. Dean Oliver is a basketball savant. He is the author of Basketball on Paper, probably the most important book ever written on basketball statistical analysis. He’s the creator of the Offensive and Defensive Ratings that are used everywhere and also the “four factors”. In Basketball on Paper he has a little section in Chapter 6 titled “Does rebounding win games?”. I thought in light of the rebounding discussion since the Chicago game has been especially hot I would hit the highlights from Dean’s analysis.
Below is a copy of analysis Dean conducted where he took the games from 1998-2002 and began to see what the ultimate win percentage was for a given team when it won a given stat category. For example, the team that won the field goal shooting percentage against it’s competitor won 4,595 games, lost 1,132 games, (33 times they were tied in FG%) so that the team that won FG% won the game 78.7 % of the time (just read across).
| Category | Won | Loss | Tied | Win % |
|---|---|---|---|---|
| Field Goal % | 4595 | 1132 | 33 | .801 |
| Assists | 4007 | 1414 | 339 | .725 |
| Def. Rbds. | 3984 | 1485 | 291 | .717 |
| Ass./Turn ratio | 3991 | 1717 | 52 | .697 |
| Total Rbds. | 3526 | 1959 | 275 | .636 |
| FT's made | 3453 | 2022 | 284 | .624 |
| Blocks | 3182 | 1930 | 648 | .609 |
| Free Throw att. | 3358 | 2174 | 228 | .603 |
| Fewer fouls | 3256 | 2094 | 410 | .601 |
| Steals | 3148 | 2037 | 575 | .596 |
| Fewer Turns | 3114 | 2186 | 460 | .581 |
| Free throw % | 3224 | 2459 | 77 | .566 |
| Offensive rbd. % | 3205 | 2513 | 42 | .560 |
| Offensive rbds. | 2452 | 2900 | 408 | .461 |
Take a minute and digest what the data is saying. It’s telling us that offensive rebounds (and offensive rebounding rate-the percent of available offensive rebounds the team collected) had the weakest relationship with wins.
You might also notice that defensive rebounds are up near the top of the list. How do defensive rebounds correlate more closely with wins than do offensive rebounds? Dean explains that the relationship between defensive rebounds and field goal percentage blurs the value of the defensive rebound.
Oliver goes on to go micro with the data and look at how important each statistic correlates with wins when two teams are roughly even on field goal shooting percentages. I will save myself from creating another table and just tell you that offensive rebounding moves up the list to somewhere close to middle. Interestingly, when two teams meet that shoot evenly free throws made and fewer turns rise to the top of the list. Blocks and defensive rebounds drop to the bottom.
You could hypothesize and rabbit trail with the data a thousand ways to Sunday if you were so inclined but I will just repeat what Oliver wrote to close: “So, is rebounding important to winning games? Of course it is. Is it as valuable as shooting, getting to the line or controlling the ball (turns)? In the NBA it doesn’t appear to be so, though as mentioned above offensive rebounds do help to improve shooting percentages…”
We, as a middling at best offensive team could use all the Orebs we can get because they give us another whack at making a basket or getting to the line, but they aren’t the deal breaker to wins and losses.
