Wingspan in the NBA

NBA players are known for their freakish size. Average height in the league has been six foot six or seven since the early 1960s, but the wingspan of NBA players is even more extraordinary than their height. According to David Epstein, the average person’s wingspan it slightly longer than their height, with a ratio of about 1.01:1. In the NBA, the average ratio is 1.05:1.

Some players have ratios much larger than this, allowing them to play bigger than their size. The average NBA shooting guard is 6’5, but Donovan Mitchell plays the position at 6’1. One factor that allows Mitchell to play above his height is his length. Michell’s 6’10 wingspan gives him a wingspan to height ratio of 1.12:1, well above the league average. This extra length helps him guard players who are taller than him, and may be a reason he averages about a steal and a half per game for his career

It is common belief that wingspan directly impacts performance, especially on the defensive end of the floor. As a result, many teams prioritize filling their rosters with length, not just height. 

But does wingspan actually have an impact on team defensive success? To find out, I calculated the average wingspan to height ratio for each team in the 2018-19 season. I used data from the NBA Draft Combine Anthrometric to find each team’s average ratio for the five players who played the most minutes last season. I then compared these averages to adjusted defensive rating (DRtg/A) from the 2018-19 season. I used DRtg/A because it is an estimate of points allowed per 100 possessions adjusted for strength of opponent offense.  

Average Wingspan to Height Ratios for Each NBA Team (2018-19)

After performing a linear regression of the data there does not appear to be a significant relationship between wingspan and team defensive success. According to the regression, team average wingspan to height ratio can only explain about 10 percent of the variation in DRtg/A. This finding could challenge the conventional belief that emphasizes the importance of wingspan, especially as a determinant of defensive prowess.

However, there does appear to be some correlation among the best defensive teams from last season. Out of the five longest teams from last year, three of them are among the top five for 2018-19 DRtg/A. This suggests that some elite defensive teams are exceptionally long, but length alone can’t make a team great defensively. 

Although team wingspan may not be a good predictor of DRtg/A, it does have some impact on deflections. Of the top five teams in deflections last year, four were also in the top ten for wingspan to height ratio. Wingspan on its own can’t effectively predict a team’s defensive success, but perhaps taking into account other factors such as deflections, charges drawn, and coaching would provide a more accurate picture of defense in the NBA.

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The Madness of 1 Seeds

March Madness is an event that captivates a huge crowd, with millions of brackets submitted every year trying to pick the winner of the 68 team tournament that ends the college basketball season. 60 teams are placed into the bracket in one of four regions, with a seed between 1 and 16 (1 is the best), and four play-in games select the last teams to get into the bracket.

A committee has selected the seeds of every team in the tournament since 1979, and the only major differences in the tournament between 40 years ago and now is the number of teams that are in it, and the removal of byes for highly seeded (1-4) teams before the 1985 tournament. The total number of teams was 40 in 1979 and quickly rose to 64 by 1985, to get our current format of four regions with 16 teams each.

Being the 1 seed in a region is a privilege that only the best teams get, and they are the favorites to win the tournament each year, as expected. It would be easy to say the teams with the best record get to put the coveted “1” next to their team, but where exactly do these teams come from, and are they as good in the tournament as they’re expected to be? Data was collected from a basketball reference affiliate on every team to have been a 1 seed from 1979 through 2019 to see how 1 seeds are historically selected and how they perform as a whole and over time. Computations were performed in Excel.

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NBA 3-Point Revolution

The importance of the three pointer in the NBA is at an all-time high. Spurs coach Gregg Popovich emphasized how the game has evolved, “Now you look at a stat sheet after a game and the first thing you look at is the threes. If you made threes and the other team didn’t, you win. You don’t even look at the rebounds or the turnovers or how much transition D was involved. You don’t even care. That’s how much an impact the three-point shot has and it’s evidenced by how everybody plays.” This new style of play began in the 2012-2013 season, when the average three point attempts per game began to spike, and it has been on a steady climb ever since.

What caused this sudden shift to the perimeter? One explanation comes from analytics. Points per shot (PPS), which calculates points scored per field goal attempt (Total Points)/(Total Field Goal Attempts), is one of the best measures of a player’s efficiency. PPS can also be used to determine the places on the court where shooters are most efficient from, providing a reference for where teams score most efficiently. Tracking PPS by location over from 2013-14 to 2017-18 showed that only shots in the paint are worth more than three pointers. The corner three (22ft instead of 23.75 ft) is only behind the restricted arc in PPS. As a result, teams are opting to shoot more threes instead of less efficient shots like mid-range jumpers.

This sudden change in offensive focus has impacted the makeup of the typical starting five in the NBA. Teams no longer have a single three point specialist, and it is common for an entire lineup to be a threat from deep. The Golden State Warriors’ “Death Lineup” of Stephen Curry, Klay Thompson, Kevin Durant, Draymond Green, and Andre Iguodala is the most famous example of a small ball lineup in the modern NBA. Curry and Thompson both shoot over 40 percent from three, and are considered two of the greatest shooters ever. Durant is another elite three point shooter (38 percent), and Green and Iguodala are both around 33 percent, which forces defenses to at least respect them from deep. This type of lineup causes an unprecedented amount of spacing, since opposing defenses are not able to help because every player is able to shoot the three. For comparison, here is the 1995-96 Chicago Bulls starting five and their career three point percentages: Harper (28 percent), Jordan (32.7 percent), Pippen (32.6 percent), Rodman (23.1 percent), and Longley (0 percent). Steve Kerr, the current coach of the Warriors, was the only player to shoot over 40 percent from three on this Bulls team.

In the new perimeter-centric NBA there are fewer big men who play with their backs to the basket. There is now a new brand of frontcourt players who can shoot from range, and some of the most prominent stretch fours and fives in the league today are Karl-Anthony Towns, Kristaps Porzingus, and Brook Lopez. Each of these seven-footers averages at least five three point attempts a game, a number of attempts that the three point specialists of the early 2000s would average. 

Stephen Curry is perhaps the one player who is most responsible for the three point revolution. In the 2012-2013 season Curry made 272 three pointers, breaking Ray Allen’s previous record of 269. Three years later Curry shattered his own record, making 402 threes. Curry owns five of the top ten seasons with the most threes made in NBA history, including three of the top four. While Curry is groundbreaking in the number of threes he makes, he also belongs to an elite group of deep three point shooters. Last season the trio of Curry, Damian Lillard, and Trae Young combined to make 71 of 186 threes from 30 to 40 feet, a 38% clip well above the league average (25.9%) at this range. 

Although it is more difficult than ever to make the league without shooting the three, there are still players who are effective without being three point marksmen. Elite rim protectors like Rudy Gobert, Hassan Whiteside, and Derrick Favors are all able to play without stretching the floor, perhaps because of their ability to prevent easy baskets in a spaced modern NBA. 

Ben Simmons is one of the few NBA guards who does not shoot threes. The six foot ten point guard has never made a three in his career, nearly all of his points come in the paint on drives or in transition. Other guards like Rajon Rondo have tried to add the three pointer to their games, since the majority of backcourt players coming into the league now are able to shoot.

Note: All statistics are from Basketball Reference, unless linked to another source.

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