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The Intersection of Shot Defense, Location, and Clock (DLC)

Is it better to shoot early in the shot clock? What if the shot is contested, is it still better to shoot early? How does shot location influence the decision to shoot? Is it better to attempt an open mid-range shot early in the shot clock versus a contested shot near the basket late in the shot clock?

These are likely some of the decisions going through players’ minds when they decide to shoot, even if they don’t realize it. The last example is particularly interesting because it gets at the crux of shot selection: the player has an open mid-range shot, but is it worth passing that up to get a potentially contested shot near the basket later in the shot clock?

There’s been previous research into whether teams should be shooting early in the shot clock. However, we can take this a step further and look at the shot defense faced. WARNING: this will be a lengthy exercise but there will be a number of visuals to help you along.

First, before we start, I suggest refreshing yourself on the definitions for each type of shot defense. You can find that here. Done? Let’s start off by looking at how FG% changes given the time in the shot clock and the type of shot defense.

Note: Shot Clock values are time remaining

 

As we can see in the graph, the earlier you can shoot in the shot clock, the more likely you are to make the shot. This is true for basically all forms of shot defense (the exception being altered, where the sample size is pretty small and filled with bad shots taken after shot-clock resets often in desperation). Is there a particular reason for this? Certainly, we can posit that players rush their shots at the end of the shot clock, which may lead to the diminished FG% (labeled Panic Room in the graph). However, what about the increase in FG% even as we get away from the “late in the shot clock” area? Well, one reasonable assumption is that players who shoot early in the shot clock are likely in transition (labeled Transition in the graph). It could be that a majority of the open/guarded/pressured shots that are being taken early in the shot clock are shots that are close to the basket causing a higher FG%. But what about the contested shots? Whether the player is in transition or not, a contested shot has a lower chance of going in, especially near the basket.

There are a few issues with the graph presented above: first, there is no adjustment for the 3 being worth one more point. This is easily correctable: we’ll look at points per shot instead

The graph above looks mostly the same with the differences between open and contested shots better defined. The second issue we have with both graphs is that the sample size on the ends are considerably smaller and it’s particularly clear with altered shots where there were only four altered shots taken at 24 seconds in the shot clock. This is why you see that big nosedive for altered shots at 24 seconds. So let’s fix this issue by creating 5-second bins for each type of shot defense. The graph is below:

 

We can see that regardless of shot defense, if you shoot earlier in the shot clock, the PPS goes up. There is also a drastic increase from the 16-19 seconds to 20-24 seconds bin for guarded, open and pressured shots. As I alluded to earlier, it’s likely that many of those shots are occurring close to the basket in transition. So we’ll need to break it down even further by shot location. But before we do that, I think it’s important to note that for altered and contested shots, we still see a steady increase in PPS as you shoot earlier in the shot clock. It’s possible that a lot of the shots in the 20-24 second interval are still in transition but because the shot is being contested, I’d argue a shot in transition is irrelevant. We know contested shots near the basket have a much lower chance of going in.

Before we break down the graphs by shot location, let’s first look at the distribution of shot defense at each second:

 

This graph may seem a bit confusing but what the graph shows is approximately 50% of the shots taken at one second were contested while almost 20% of the shots taken at one second were pressured. If you add up all the points for each level of shot defense at one second, it will be 100%. So what does this graph tell us? The majority of the shots taken are contested and as the shot clock winds down, the rate of contested shots goes up. In regard to the end points (such as 24 seconds), keep in mind the sample size for these points are going to be much smaller so that’s why you see some odd spikes or nosedives at that time interval.

Now let’s move onto looking at the shot clock and shot defense with respect to the shot location. As I mentioned earlier, it’s likely that a lot of the guarded, open and pressured shots early in the shot clock were coming near the basket in transition.

So we can remove the shots that were near the basket and look at only mid-range shots and three point shots. This should essentially remove the effects of transition offense since most players attack the basket in transition.

 

Again, we can see that shooting at the end of the shot clock is not recommended. However, perhaps what is most interesting is that at one second, the chances of making the shot are essentially the same across all levels of shot defense. The sample size is not ideal– about 220+ shot attempts for open and guarded– but it’s large enough that we should feel comfortable drawing some conclusions. If you are wondering why the graph only goes to 23 seconds, it is because I removed shots taken at 24 seconds due to a very small sample size (22 total shots).

Let’s also take a look at the distribution of these shots at each time interval:

 

Like the first graph, we see that the majority of shots taken from mid-range or three are contested.

Now, let’s look at mid-range shots and threes separately since the value of each shot is significantly different. First, we’ll look at the dreaded mid-range shot. How does FG% vary for mid-range shots over time in the shot clock?

 

We see that FG%’s decline as the shot clock winds down with the exception of open and guarded shots at one second. However, the reason for this is simply due to a small sample size– less than 100 shot attempts for both open and guarded shots at one second. In fact, we have some sample size issues on both ends of the graph so let’s look at the same graph but with five second binned intervals:

 

We’ve removed some of the sample size issues from the previous graph (although as you can tell, there are still some issues with guarded and open shots from 20-24 seconds, where fga is 140 and 165, respectively) and we can continue to see that it is advantageous to shoot earlier in the shot clock. In fact, contested mid-range shots taken with 16-24 seconds remaining are more likely to go in than guarded shots taken with 1-5 seconds remaining and almost as likely to go in as guarded shots taken with 6-10 seconds remaining.

How about the distribution of shots taken at each second?

 

Again, we see that as the shot clock winds down, we see more and more contested shots taken. After looking at this graph, I’m sure you are left wondering how often is the “worst shot” taken? (If you are wondering what the worst shot is, it’s a contested mid-range shot taken with 1-5 seconds remaining) Over the last two years of shots that Vantage has tracked, the “worst shot” was attempted 4% of the time. If we include pressured mid-range shots taken with 1-5 seconds remaining, that number jumps to 5.2%.

Let’s move on to exploring three-point shots and how the FG% varies over the shot clock. Like before, we’ll look at the FG% for the different types of shot defense:

 

As I mentioned in the previous article, we can see the difference between open and guarded shots versus contested shots. We also see that for pressured shots, there seems to be a pretty high fluctuation from second to second. As I did in a previous graph, I had to remove the 24 second interval as well as some of the values for the 23 second interval due to sample size issues. Let’s fix those issues by looking at the 5-second binned intervals:

 

This is the first graph where we can’t really see any effect of shooting earlier in the shot clock. We do see that in the 1-5 second bin, FG% is at its lowest. However, there is no trend among any of the other bins. So if a team wants a three, it does not matter when in the shot clock they shoot it. Another interesting conclusion we can draw is that there seems to be a significant difference in the FG% for shots taken in the 1-5 second bin across each level of shot defense. We see that going from a contested three to a guarded three can raise your FG% by about 7% and going from a guarded three to an open three can raise your FG% by 5.5%. So if a shooter is able to get a wide open three within the last five seconds of the shot clock, it will still be very beneficial to the offense. We also see that a guarded three taken in the last five seconds of the shot clock doesn’t have a much higher chance of going in than a pressured or contested three taken earlier in the shot clock.

Let’s look at the distribution of shot defense at each time interval:

 

Again, contested threes are the most likely shot and the rate of contested shots goes up as the clock winds down. Players are also attempting more open threes with 15-22 seconds remaining on the shot clock.

Finally, let’s look at shots close to the basket. When looking at the FG%, keep in mind that many of the shots early in the clock may come in transition. However, if the level of shot defense is the same, should the shot being in transition really inflate the FG%? I’ll let the reader decide when looking at the graph.

 

This graph may be the best visualization of the research conducted in my first article. The difference between getting a contested shot near the basket and a pressured shot near the basket is night and day. And the difference between getting a pressured shot and an open shot (which will mostly be layups or dunks) is also night and day. In regard to the shot clock, there doesn’t appear to be any difference between getting an open shot early in the shot clock as opposed to late: it’s about a 90% proposition either way. This isn’t entirely surprising since a dunk with five seconds left in the shot clock is as likely to go in as a dunk with 20 seconds left in the shot clock. However, there is a difference for every other level of shot defense. We see that guarded shots taken early in the shot clock are as likely to go in as open shots taken late in the shot clock while pressured shots taken early in the shot clock are as likely to go in as guarded shots taken late in the shot clock. We also see that the FG% for contested shots seems to gradually increase as well. Still, like many of these graphs before, we do have a bit of a sample size issue (especially the guarded and open shots). So let’s look at the same graph with five second binned intervals:

This graph is a bit easier to interpret and we see that for every level of shot defense with the exception of open shots, FG% goes up as you shoot earlier in the shot clock. We can also see that as you move “up” each level of shot defense, a player is more likely to make the shot.

As we’ve done before, let’s look at the distribution of shot defense at each time interval:

 

This graph is different from some of the past ones we’ve looked at. Early in the shot clock, there are actually more pressured shots attempted than contested shots. There are also more open shots attempted early in the shot clock. Like the past graphs, the rate of contested shots goes up as the time on the clock elapses. Players also foul less as the shot clock winds down- clearly a bright idea. Although it is interesting that block rate increases as the shot clock goes down. Despite the higher rate of blocked shots, players are still able to foul less.

Let’s answer some of the questions posed at the beginning of this article.

Is it better to shoot early in the shot clock?
I think the evidence certainly points to this. However, for three point shots, there doesn’t appear to be any advantage for shooting early.

What if the shot is contested, is it still better to shoot early? How does the shot location influence this?
At first glance, it is certainly never a good idea to shoot a contested shot. However, for mid-range shots and threes, there is a cutoff point where contested shots early in the shot clock are basically as good as guarded or open shots late in the shot clock. For mid-range shots, that cutoff appears to be around approximately 10 seconds. For threes, that cutoff point only applies to guarded shots and occurs at around approximately five seconds. Of course, I’m only eyeballing the cutoff point based on the binned graphs so it would be an interesting exercise to determine the exact cut off point. But to answer the question above, it is not better to shoot a contested shot early. However, if you are going to wait for the shot clock to go all the way down, you may as well shoot that contested shot.

Is it better to attempt an open mid-range shot early in the shot clock versus a contested shot near the basket late in the shot clock?
We can take this last question one step further and look at contested threes as well. In order to compare the three types of shots, let’s look at our last graph:

 

In looking at the graph, it is pretty clear that open mid-range shots are never preferable over contested threes or close shots. However, at each end, we do see that the PPS for contested threes and open mid-range shots are nearly the same. If the shot clock is winding down to near zero, it isn’t a horrible idea to step in a few feet and shoot the mid-range jumper. Likewise, if you have an open mid-range shot early in the clock, instead of stepping back and risking it being contested, you may as well take the open shot. Otherwise, contested threes and contested shots near the basket are better bets than open mid-range shots.

Unfortunately, for those clamoring for the mid-range shot to remain a big part of the game, there isn’t much here to support your claim. In fact, the evidence here seems to point to mid-range shots being completely abandoned. Still, it is important to break this down further by each specific shot location. Perhaps there are areas of the mid-range game where shooting an open shot is better than shooting a contested three/close shot. Additionally, each player is going to have different percentages. While the league as a whole should be shooting less mid-range shots, for a specific player, this graph may look much different.

Also, since I mentioned that the league should be shooting less mid-range shots, what exactly does the distribution of shots look like?

 

As expected, the rate of close shots goes down as defenses are able to set up and protect the basket. We also see the rate of mid-range shots increase till about 15 seconds at which point it levels off at around 40%. Instead, we see the rate of threes increase as the shot clock winds down.

Bonus question: What about contested threes versus contested shots near the basket?
Perhaps the more interesting part of the first graph is looking at contested threes versus contested shots close to the basket. If we look at the best fit lines (the solid lines with no points) for contested threes and contested shots close to the basket, we see that contested threes are preferable to contested shots near the basket from about 19 seconds remaining to about 5 seconds remaining. However, if it is either early in the shot clock or late in the shot clock, it is better to shoot a contested shot near the basket than to take a contested three.

If you have any questions, comments or suggestions, please reach me on twitter @knarsu3

Note: Shot locations were defined as followed:
Close shots were shots taken in locations t,u, and v
Threes were shots taken in locations a, b, c, d, and e. Locations aa, bb and cc were removed due to them being past half-court.
Mid-range were shots taken in locations f, g, h, i, j, k, l, m, n, o, p, q, and r
Shots in locations s and w were ignored due to not really fitting in any category. The total shots taken from those locations were about 130 apiece i.e. not a significant difference. 

The Value of Contesting Shots

The value of contesting a shot

The idea is not to block every shot. The idea is to make your opponent believe that you might block every shot. -Bill Russell

Bill Russell is one of the all-time greats in basketball. His shot-blocking ability is legendary and the NBA has never seen a player like him since. The heart of Russells quote is about effort: the daily grind of contesting every shot.

Until recently, we had no dataset that could separate the grinders from the slackers, the everyday from the spotlight-seekers. Dwight Howard is widely considered to be the player most similar to Russell, one of the best defenders in the NBA.

But Dwight is no Russell. Despite the high rate of blocks, he doesn’t contest shots nearly enough. And the difference between not contesting a shot and contesting it is huge. To examine how huge, we go to the numbers.

Vantage tracks every level of shot defense, including contested and pressured shots. Contested shots are defined as being within three feet of the shooter while getting your hand up. Pau Gasol contesting a shot:

The End of Assists & The Best Facilitators in the Draft

According to most public draft boards, Phil Pressey is a late 2nd-round pick. There are legitimate concerns with his game, including his scoring and turnovers (however, his 4.5% tunovers per touch is still lower than plenty of starting guards in the NBA – including Chris Paul at 5.0%). Despite these concerns, our data indicates that Pressey may be the first or second best facilitator in this year’s draft.

Ignore Assist Numbers

Traditionally, the only number used to judge a player’s ability to facilitate the scoring of teammates has been assists. Here are the assist numbers for Michael Carter-Williams, Trey Burke, and Phil Pressey

Michael Carter-Williams: 7.3
Phil Pressey: 7.1
Trey Burke: 6.7

These numbers tell us that Carter-Williams was the most productive facilitator, with the spread between them being only 0.6 and Pressey only producing 0.4 more assists per game than Burke.

However, looking at assists alone may mislead us in a number of ways:

(a) it does not take into account the ability of teammates to make shots.
(b) it does not take into account the level of shot defense applied to made shots.
(c) it does not take into account most passes to shooting fouls, as assists are not given when the shooter is fouled and misses the shot as a result.
(d) it does not take into account passes before the assist that were just as crucial as the assist.

The drawbacks of the assist stat can lead to faulty analysis which cannot be easily or accurately accounted for with mathematical adjustments and assumptions.  Vantage Data and the following Vantage Stats attempt to correct these distortions and provide insight into this year’s crop of facilitators.

Assist+ Per 100 Chances: Pressey Impresses

Assist+ is a number that tracks not only traditional assists, but also gives credit to a passer when:

(a) a pass results in a shooting foul
(b) a pass results in a missed open shot (attempts to de-penalize facilitators for teammates’ poor shooting on open shot attempts)
(c) a pass is deemed crucial to an assist or a subsequent pass resulting in a shooting foul. Crucial passes can be thought of as “hockey assists,” or assists-to-assists.

This number provides a more holistic view of a facilitator’s ability and is a good place to start the analysis.  The top 3 in Assist+ in this year’s draft class are as follows:

Phil Pressey: 14.2
Michael Carter-Williams: 11.5
Trey Burke: 11.1

Pressey’s rate of production is #1 and 23% higher than Carter-Williams. Further, as stated above, one of the big problems with assists in general is the lack of adjustment for the shot defense faced by teammates. This means that a player can rack up high assist numbers just by passing to covered teammates that make contested shots, and our numbers show this is exactly the case with Michael Carter-Williams.

True Facilitation: A Shot Defense-Adjusted Standard

True Facilitation is the number of passes to uncontested shots per 100 offensive chances, regardless of whether the shot is made or missed. In other words, it excludes those assists where the shooter made a contested shot, but includes passes that resulted in missed uncontested shots. Therefore, True Facilitation is the best measure of a passer’s ability to “find the open man.”

Watching a few of Rajon Rondo’s passes to open shots makes it clear that – until now – we’ve been undervaluing the facilitation ability of players that can do this consistently.

Here are the True Facilitation numbers for the top 3 Assist+ guys:

Trey Burke: 3.05 (#1 in TF)
Phil Pressey: 2.2 (#2 in TF)
Michael Carter-Williams: .738 (#23 in TF)

Pressey trails Burke, but is still #2 in the draft, but we see a major drop-off for Carter-Williams. This means that Carter-Williams’s teammates were good at making contested shots, not necessarily that he was good at getting his teammates good looks.  This is a red-flag for those interested in Carter-Williams, and a confirmation for those interested in Pressey.

How They Facilitate 

The Vantage data set is capable of providing even deeper analysis than these new metrics on facilitation. And we hope you’ll forgive us for diving a bit deeper here, but we think it is important to understand how these guys are facilitating opportunities for teammates.  Are they simply standing on the perimeter and reversing the ball?  Are they playing off a screen or driving?  Understanding how guys produce is extremely important in assessing fit for specific teams.

Again, for the three players we’ve been highlighting, here are the %’s of their Assist+ generated through the drive, screen, into the post, and in transition:

The outlier is, again, Carter-Williams.  Whereas both Pressey and Burke generated about the same number of facilitations via screens and drives, Carter-Williams thrived in transition and drives, not utilizing the pick and roll as much.

Here’s a look at a few of Pressey facilitations off screens:

and off the drive:

Pressey and Burke are a close 1-2 in terms of best facilitators in this years draft.  While Pressey has the higher assist+, Burke has the higher True Facilitation, and both produce in similar ways.

More New Metrics to Come

We are using these posts as a friendlier introduction of Vantage’s capabilities than just providing data dumps or full scouting reports of individual players. If you missed any of our prior posts about new statistics, please check them out below and check back regularly (or follow on twitter) for the rest of the introductions.

And for those following along at home (admit it – you’re at work), enjoy the draft!

1) Scoring
2) Facilitation
3) Rebounding
4) Screening
5) Turnovers and Fouling
6) Shot Defense

  • Contest+
  • Points Allowed Per Shot
  • Shots Defended Per Chance
  • Overall FG% Against

7) Disruptions

  • Turnovers Forced Per Chance
  • Deflections Per 100 Chances
  • Passes Denied Per 100 Chances
  • Pressure Rate

8) On-Ball/Screen Defense

  • Keep in Front %
  • Close Out Points Allowed
  • Points Allowed Per Screen
  • Effective Screen Defense Rate

9) Help/Double Team Defense

  • Double Teams/Helps Per 100 Chances
  • Points Allowed Per Double Team/Help
  • Effective Double Team/Help Rate

10) Movement and Involvement

Pick-and-Roll Defense: The Switch

The pick-and-roll is one of the most common actions youll see across the league. How a defense handles the pick-and-roll goes a long way in determining how effective most offenses can be. Using Vantages dataset from this season and last, lets take a look at how teams employ one of the more unique pick-and-roll defenses: the switch.

The table below shows the how NBA teams defend on-ball screens. On most occasions, a defense will provide some level of help (hedging or retreating into the paint), and then expect everyone to recover to their original defensive assignments. The Wizards have employed this strategy the most (72 percent of the time) across this two-year period. A defense can also double team the man coming off of the ball-screen to try to create a turnover or force the ball out of the ball-handlers hands. This has been most popular with the Bucks, who double team the ball-handler on about 30 percent of ball screens.  Finally, defenses can simply switch on the screen. The defender that gets screened doesnt try to stick with his man, instead he guards the screener, while the help defender guards the ball-handler. The Knicks lead the league in switches.

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Some coaches dont like switching because of the mismatches it creates; having your bigs guarding the perimeter and your guards defending the post is not ideal. But depending on your personnel, it can be a good option. If your point guard is too slow to maneuver around screens, switching can be your last resort. If a team is stocked with similarly-sized players and/or a mobile frontcourt, those mismatches created in a switch may not be mismatches after all. Lets take a look at how often teams are switching and how effective their defenses are.

The table below shows how successful teams are when they switch on pick and rolls. The first column shows how often teams switch ball screens, its the same data as in the table above. The next two columns show the results of those switches, whether they be good or bad. For our purposes, we are considering good defensive play to be a forced turnover, a contested shot, or not allowing any event, such as a shot, assist, foul, etc. A bad defensive play is allowing an open shot, a made shot, an assist, or committing a foul. The fourth column shows how often the defense forces a turnover when switching.

 

 

Some takeaways from the data:

  • For the most part, the teams that do the most switching are the most successful at it. The Knicks, Warriors, and Nuggets lead the league in ball screen switches and are all above average at defending when they switch. Each team may have different reasons for their switches. The Nuggets have an army of athletic swingmen, which is perfect for switching, while the Knicks point guards can be a bit limited on defense and may have trouble fighting through screens.
  • The Knicks, under Mike Woodson and Mike DAntoni, have been the the most likely team in the league to switch defensive assignments on a ball screen. This is for good reason, as they are also the team with the most good defensive plays on switches. They arent masterful at forcing turnovers or contesting shots, they simply dont allow shots; no event occurs on 52 percent of their switches.
  • The Lakers and the Wizards are also quality defenders after switches, but they do it in a different way than the Knicks. Offenses are more likely to get off a shot against Los Angeles or Washington, but these two teams have been the best at contesting those shots.
  • The Dwayne Caseys Raptors are the rarest switchers in the league, but they arent particularly bad when they do. Because Andrea Bargnani has struggled so much with help defense, it might be wise to employ more switching to reduce help defense-related mistakes.
  • The Bucks and Kings play the worst defense when they switch, but at least Milwaukee has limited the amount of times that they switch. The Kings, on the other hand, switch ball screens an above average amount of the time. After a switch, the Kings give up an open shot to either the ball handler or another player more than 25% of the time.
  • The Hawks and Heat are the best at stopping the ball handler from shooting after a switch. Both of these teams have utilized smaller lineups with some success, and having Lebron James, Josh Smith, or Al Horford switching on to your point guard can be much scarier than facing the average big man switch.
  • The Grizzlies are the best at forcing turnovers after switches. That should be no surprise, as they are usually among the best in the NBA at forcing turnovers in general. Known for his quickness despite his size, Marc Gasol has forced turnovers on 10 percent of his switches.

Overall, switches are sparingly used across the league, but there are a few teams that utilize it more than others. Looking at lineup data combined with pick-and-roll coverage data could provide a window into how coaches regard the defensive abilities of their players.

Jason Collins’ Revelation and the Top Screeners in the NBA

Jason Collins and the Box Score

Jason Collins said something last spring that we here at Vantage Sports have been waiting to hear an NBA player admit for a long time. Spoiler alert – it had nothing to do with his sexual orientation.

“My contributions don’t show up in the box scores.”

What Collins meant is that his game involves moves that improve other players’ box scores. As he explains, “I set picks with my 7-foot, 255-pound body to get guys like Jason Kidd, John Wall and Paul Pierce open.”

Screens are crucial to every team’s success. Screens are the only tool a player has to legally contact a defender, creating space for a teammate to either score or facilitate a score. Collins’s abilities have been rewarded with an NBA salary for more than a decade, yet have never been effectively tracked or measured.  Notice that there is no “effective screens” line item in your NBA box score. Vantage Stats changes that by measuring both screening effort and efficiency.

Solid Screen % and Screens Per Chance

A good screen requires more than a big body (or as John Stockton proved, a not-so-big body).  The fundamental job of the screener is to create space either through contacting the defender or forcing the defender to adjust his path.

Vantage tracks a player’s “Solid Screen %”. This is the percentage of set screens (both on-ball and off-ball) where a player either makes contact with a defender, or re-routes that defender.  This statistic excludes slip screens (times where the screener rolled or popped prior to the receiver getting to the screen).

Here are the top 5 NBA big men in Solid Screen % over the past two seasons (with minimum offensive chances and screen attempts) along with their Screens Set Per Chance:

1. Ronny Turiaf (79% Solid) (.49 per chance)
2. Nick Collison (78.3% Solid) (.44 per chance)
3. Marcin Gortat (78% Solid) (.63 per chance)
4. Joakim Noah (77.5% Solid) (.47 per chance)
5. Kenyon Martin (77.2% Solid) (.42 per chance)

Set Screen Points Per Chance 

“Set Screen Points Per Chance” is the number of points per offensive chance created by player’s set screens.  This is the cash-out value of a player’s set screens in terms of points scored by his teammates. Another way to think of this statistic is like a non-passing assist.

Here are the top 5 NBA bigs in Set Screen Points Per Chance over the past two seasons (again, with minimum offensive chances and screen attempts):

1. Tiago Splitter (.123 points per chance)
2. Kendrick Perkins (.117 points per chance)
3. Joel Anthony (.11 points per chance)
4. Tyson Chandler (.108 points per chance)

5. Marcin Gortat (.107 points per chance)

Your mind is probably jumping ahead of itself at this point, thinking about the scorers using those screens, right? Indeed, Tony Parker’s uncanny/gymnastic/otherworldly scoring ability might be inflating Splitter’s numbers here. And full disclosure: Duncan is #6.

This metric therefore suffers from the same bias that box-score assists do. You can’t control your teammates’ ability to hit shots in open space, and those that are surrounded by great scorers are going to look like better screeners in this context. But combined with other metrics, this can be a powerful signal in evaluating underlying factors of offensive efficiency.

Set Screen Outcome Efficiency

One way to correct “Set Screen Points Per Chance” is to look at screens leading to a more broadly defined set of “good” outcomes.  “Set Screen Outcome Efficiency” does exactly that.  It is the percentage of set screens that result in a teammate score, missed open shot, shooting foul or Assist+ (see our earlier post on passing).
Here are the top 5 in Set Screen Outcome Efficiency (again, adjusted for minimum offensive chances and screen attempts):
1. Carl Landry (49%)
2. Joakim Noah (48%)
3. Andrew Bynum (47.9%)
4. Jason Maxiell (44.8%)
5. Kendrick Perkins (44.7%)

Putting It All Together: Noah Is the Best

3 names appear twice in the 3 lists above, Joakim Noah is in the top 5 in both Solid Screen and Outcome Efficiency. Marcin Gortat is in the top 5 in Solid Screen and Points Per Chance. Finally, Kendrick Perkins is in the top 5 in Efficiency and Points.

Noah’s Points Per Chance is at .064, which is nowhere near the leaders in that category. However, he stands out as the best high volume screener in the league.  This is because Set Screen Outcome Efficiency is more screener-dependent than Points Per Chance and the best way to judge screen value independent of teammates’ performance. Noah excels in setting solid picks resulting in good outcomes for the Bulls.  With Derrick Rose back on the court look for Noah’s Points Per Chance number to jump.

Here are a few Noah highlights to get you ready for the season:

Conclusion

Statistics are important because they tell stories. Stories about how much we should value players, who we should praise (or ridicule) and how players are most (and least) effective. Vantage Sports started with the premise that traditional statistics fail to tell the most compelling stories.

Vantage Stats aims to improve the ability to measure performance and track the most meaningful aspects of the games we love. We hope the Jason Collins of 2016 can say, “Clearly, you should sign me. My Solid Screen %, Screen Points Per Chance, AND Set Screen Outcome Efficiency are all off the charts!” In case you were wondering, though he didn’t have the sample size to make it, the Jason Collins of 2012 was a very good screener, posting an 82% Solid, .069 Points Per Chance and 39.5% Outcome Efficiency.

The Corner Three

Of all the potential shot attempts, a three-pointer from the corner is one of the best shots an offense can get. Across the league, players shoot at a higher percentage from the corner than from other spots around the three-point arc. One obvious reason is that it is the shortest distance three-pointer available. But what about other factors that can affect shooting percentages, such as how the defense reacts to the shot or whether the shooters’ feet are set? Using Vantages dataset from this season and last season, lets take a look at how shot defense and shooter movement change from different spots around the three-point arc.

Shot Defense

Because of some teams defensive rotations and their willingness to leave certain shooters alone in the corner, it is worth investigating whether the average corner three is met with less defensive resistance than other threes. If corner three point shooters are getting wide open looks while shooters from other locations are getting their shots contested, then that could help explain why players hit corner threes at such a high rate. The corner three might not be that easy, its just that defenses are giving up open shots in the corner and guarding the threes around the wings and top of the key.

The chart below shows how often shooters from the different locations see various levels of shot defense.  “Contest+” includes when defenders block the shot, alter the shot, or are within three feet of the shooter with their hand up. “Pressured” indicates when the defender is within three feet of the shooter without a hand up, “Guarded” is in between three and five feet of the shooter, and “Open” is when a defender is outside five feet.

 

As the chart shows, defenses are challenging shots in almost the exact same ways from each of the locations. Regardless of location, roughly half of three point attempts are strongly contested, and the other half are split about evenly among the remaining categories. So we know that defenses arent forgetting to contest three point shots, even when they are being launched from the corner.

To further explore the numbers, here are the shooting percentages by location and level of shot defense.

When defenses are strongly contesting the shot, the corner three loses some of its appeal. Shooters are hitting 33 percent of their strongly contested corner threes, about the same as a three from the wing. However, once the level of defense drops off, the corner three gets much more dangerous. When a defender simply cant get a hand in the face of a corner shooter, the percentages jump up to 38 percent, and continue rising above 40 percent as the defense gets worse. On threes from the wing and top of the key, the percentages dont start looking good until the defense gets really lax.

Number of Dribbles

Another reason corner threes may be generally easier than threes from other locations is that a player is highly likely to have his feet set prior to shooting when he is in the corner. Most players are much more comfortable taking jumpers with their feet set, as opposed to off the dribble. The chart below shows how often players are using their dribbles when taking jumpers from the three-point locations.

Less than five percent of corner threes are shot off the dribble. That number pales in comparison to threes from the top of the key and wing, where 37 percent and 22 percent of threes are taken off the dribble, respectively. Obviously, there is more room to move on the wings and top of the key than in the corner, so we are more likely to see shots off the dribble, with players using ball screens, crossovers, etc.

When we look at the three point percentages by number of dribbles, we can see that when players dont need to dribble, the corner three is still made at the highest rate (38 percent).

The wing three is close, at 36 percent, but the corner three still reigns supreme in terms of efficiency. Once a shooter starts dribbling, those percentages drop. While shooting off the dribble decreases percentages in any of the locations, nowhere is it more drastic than from the corner. On the rare occasion that a corner three is taken off the dribble, they are only going in 25 percent of the time. Unless its Kobe Bryant in his prime, dribbling into the corner is usually a bad idea.

If dribbling is eliminated from the equation and we only look at the difficulty of zero-dribble threes, the chart looks like this:

Conclusion

Even after accounting for shooter movement and the strength of the defense, the corner three still comes out looking like the easiest three. The big difference with the short distance corner three comes when defenders arent playing strong defense. If a shot is launched from the wing or top of the key, the defense might be able to get away with not getting a hand up. But if that three-point attempt comes from the corner, anything but great defense can turn an average shooter into a 40+ percent shooter.