How Valuable is Creating Open Shots for Teammates?

Since we now have a good way to measure creation historically, I wanted to explore the relationship between creating shots for teammates and performance. Theoretically, we’d expect there to be some positive relationship between creation and the scoreboard — the more a team can breakdown a defense, the more higher-efficiency looks they’ll have. Using Box Creation, we can test this hypothesis.

Sure enough, there is a moderately strong relationship between a team’s creation rate and its offensive rating.* In 2006, the league started moving toward its current pace and space, 3-point centric game. Since then, the correlation between Box Creation and a team’s offensive rating was a healthy 0.66. (It was 0.56 since 1980.) For some perspective, turnovers have about a 0.4 correlation with offensive rating and effective field goal percentage has about a 0.8 correlation.

Remember, a team’s creation rate is not an estimate of the percentage of open shots a team takes — teams will end up with open shots when the defense breaks down, in transition or even just from setting a bunch of screens and forcing the defense to concede a deep jumper. Instead, Box Creation is a pace-adjusted estimation of how often a team created an opportunity (per 100 possessions) that led to an open shot. So why isn’t the relationship super strong?

First, creation is about drawing defensive attention and moving defenders as a reaction to a threat. But the ball still needs to find an open shot for this to be counted as an opportunity created, and that doesn’t always happen. Poor spacing or a slow pass (or ball stoppers!) can terminate the offense’s advantage, failing to capitalize on an opening that the creator provided. In this sense, passing is a separate but related component. While it’s the next step in creation, good passing, in general, is about capitalizing on or exploiting an advantage that already exists. (That advantage can come from creation or some defensive error.) So creation rates are not entirely independent of teammate quality.

Second, teams that excel in isolation, at offensive rebounding or by screening for long shots do not rely as strongly on their creators. This speaks to one of the wonderful parts of basketball; there are many ways to skin the cat! Because of that, we wouldn’t expect the relationship between shots created and offensive performance to be that strong. However, as you can glean from the plot above, the majority of historically great offenses create a lot of shots for each other. Fourteen of the top 15 creating teams since 1978 have finished with offensive ratings at least five points better than league average.

There’s a similar, moderate relationship for individuals between Box Creation and Offensive Adjusted Plus-Minus (ORAPM). Using Jeremias Engelmann’s 2006-2011 single-year prior-informed set, the correlation between creation and ORAPM is 0.52 for individual players. Again, this is expected — being a good creator helps, but it’s not the only way to defeat defenses.

Still, the moderately strong relationship between creation and performance reflects the importance of having centerpieces on the roster who can generate easier shots for players who can’t create for themselves.

*Because of the way basketball-reference data is organized, note that this method underestimates teams that made trades. A team swapping two strong creators will be severely underestimated. 

The Best “Healthy” Offenses of All-Time

In the last post, we looked at the best point-differentials of all-time posted by teams that were “healthy” (when all 25-minute per game players were in action, minimum 41 games played together). But what about isolating the offensive side of the ball?

Since box scores aren’t readily available before 1984, we are limited to teams from the last 32 seasons. But that’s fine — 99 of the top 100 most efficient teams in NBA history played in 1984 or later. (The 1982 Nuggets are the exception.)

Before analyzing the list, a quick disclaimer to keep in mind: Offensive rating is not a perfect representation of offensive quality. Teams can choose offensive-centric lineups at the expense of defense for a net boost, such as crashing the offensive boards instead of retreating in transition defense. Below are the top offenses, relative to the defenses faced, based on these healthy lineup standards:

Healthy Offense Relative ORtg

The 2006 Suns played the second half of the season without Kurt Thomas after running out of big men. As a result, they played one of the most lopsided lineups in NBA history, starting Boris Diaw at center and three wings alongside Steve Nash. They had one big man (Brian Grant) off the bench. While they feasted on defenses, they were defensively compromised and posted an abysmal +6.6 defensive rating during these games. Given that, I wouldn’t rush to crown them the GOAT offense. Some of the Dallas teams on the list also suffer from this kind of lineup tradeoff, slotting Dirk Nowitzki at center next to an offensively-leaning forward.

Offensive rebounding has declined drastically over the last two decades as teams have sacrificed crashing the glass in order to defend transition. Some teams still crash the glass hard, but sometimes individuals are just great offensive rebounders. Dennis Rodman is the ultimate example example of this — he’ll jump a team two tiers by himself. For example, in 37 games without Rodman, the ’96 and ’97 Bulls — with Longley, Kukoc, Jordan and Pippen playing — saw a 5.1% drop in their offensive rebounding rate, which is about the difference between the best offensive rebounding team in the league and an average one.

So let’s expand the list to include components that help place a team’s offensive rating in perspective, such as offensive rebounding rate and turnover percentage. Let’s also include the raw offensive rating and true shooting percentage (TS%) of the team:

Healthy Offense Expanded

First, the 2004 Kings number is shocking because they did it without Chris Webber; they smoked the league with Brad Miller starting in place of him, a phenomenon I discuss in Thinking Basketball.

The ’96 Magic and ’16 Warriors certainly jump out as candidates for the best offenses ever. If you’re eyes thought you’d never seen anything like Golden State this year, you were right; the Warriors shooting efficiency yielded an unheard of 1.19 points per scoring attempt. The ’96 Magic were amazing too, but aided by a shortened 3-point line.

There’s a dark horse in there: The 2016 Cavs, the team that beat the Warriors. Injuries have masked an all-time level offense, led by LeBron JamesKyrie Irving and even Kevin Love. They are not in the upper stratosphere of shooting efficiency, but are a low-turnover offense (11.5%) that benefits from player-specific offensive rebounding by Tristian Thompson.

But how good is an offense that can only take advantage of a fundamentally poor defense? While most offenses perform better against weaker defenses, Cleveland has no correlation between an opponent’s defensive strength and its own offensive production. A linear regression predicts that the Cavs offense will actually perform better against elite defenses than almost every team on this list, including Golden State. Given the small samples, I wouldn’t put too much stock in this, but it is worth noting nonetheless.

Of course, there’s an elephant in the room. Where will Kevin Durant, Steph Curry and the 2017 Warriors place on this list?