The NBA Under Data Analysis
a project based on Data provided by Basketball-Reference.
Introduction
The NBA (National Basketball Association) was founded in 1949, after the merge of 2 leagues; the Basketball Association of America (BAA) and the National Basketball League (NBL). It is the most publicised league of the world.
Thanks to a huge and detailed dataset covering statistics of players from 1950 until 2017 (from Kaggle) and as a huge fan of basketball (especially about the NBA), I always wanted to investigate into the statistics of the league to showcase trends or even to answer specific questions.
Here some examples:
“The 3-Pointer has become fundamental.”
“Did Stephen Curry revolutionize Basketball?”
“Is Michael Jordan the GOAT (Greatest Of All Time)?”
Even though such questions could not be answered only via statistics and should consider unmeasurable factors (as the mindset, the mentality of the player, the investment out of basketball courts, …) I took it as challenge to reveal aspects that do not lie.
Part I. The 3-Pointer has become fundamental.
To remind readers what the basketball is, it is a team sport. Two teams of five players each try to score by shooting a ball through a hoop elevated 10 feet above the ground. It is quite easy then to understand that the closer to the basket you are, the easier it would be to score. However, recent trends show that players are more willing to shoot from far.
A shot is considered as a 3-Points instead of 2-Points if it is beyond the three-point line, a designated arc surrounding the basket (7.24 m from its center). It was officially introduced for the 1979–1980 season. It brings 3 points to the team score, compared to the 2 points of a normal shot.
Between 1980 and 2017, the number of 3-Points Attempts was multiplied by 8 (from 16 attempts to 128)!
Moreover, the largest increase is visible since 2012 and the NBA seems to head towards a game more focused on the 3-Points Shot. In fact, since 1960 the 2-Points Attempts decrease (from 689 to 273). Year after year defence has been reinforced leaving less possibilities to the players to go to the basket.
Normally, I would expect the further a shot is, the less accurate it would be. However, statistics recorded from the players over years showed me I was wrong.
The Effective Field Goal Percentage (%)
represents the efficiency of a player to bring points to his team. This statistic adjusts for the fact that a 3-point field goal is worth one more point than a 2-Point field goal.
For example, suppose Player A goes 4 for 10 with 2 threes, while Player B goes 5 for 10 with 0 threes. Each player would have 10 points from field goals, and thus would have the same effective field goal percentage (50%).
From the chart above, I could understand that players have become more and more accurate. It can be also explained by the fact NBA became more and more selective, which could only consequently raise up the whole level of the league.
As Shooters (but actually all players) have become more accurate, why not then trying to score more 3-Points instead of 2-Points (because 3 is greater than 2!), as the main goal in basketball still remains to score more points than the opposite team?
Part 2. Stephen Curry revolutionized Basketball.
And here comes the transition to Stephen Curry. After having seen that the 3-Pointer has become essential, one player is considered the bearer of this new style of play.
Stephen Curry is known to be an excellent Shooter (some discussions consider him as the best one All-Time). He plays as Point Guard (PG) and as Shooting Guard (SG) (but mainly PG). He entered the league in 2010 and he is still active today (2020).
Here is an image representing the positions in basketball.
The Point Guard is the playmaker which puts his teammates into the scoring Position. It drives often to the basket to open spaces to his team mates or to score, but it stays most of time outside of the arc.
In past, the game was more focus on Big Men (Power Forward / Center positions), because Basketball is a game of tall players. The easiest way to score remains in being close to the basket.
However, since around 2010, the game started to be more centered on the Point Guard, which showed that more than a playmaker, it could be a scorer too.
I just proved that the trend heads to shoot further, and the 3 Points Attempts is increasing strongly since 2010. Let’s dig out some valuable data on the long distance best Shooters All-Time in:
- 3 Points-Attempts Over Years
- 3 Points Percentage (%) Over Years (Field Goals Over Attempts)
- Player Efficient Rating (from the best 3 Points Shooters) — a rating developed by ESPN.com columnist John Hollinger
To consider the best 3 Points Shooters, a minimum of 4 Seasons is requested, as a minimum of 300 Attempts for the career in average.
- Most of the top 3-Point Shooters in Attempts are from the last decade.
- Ray Allen and Reggie Miller seem to be the precursors of the long distance shooting (the only players, except Kyle Korver not from the last decade). That’s also one among many reasons why they are considered within the best shooters; precursors, stable statistics, longevity as a shooter, ...
- Stephen Curry leads the ranking from attempts (in relation to the number of active years) and has a very high % of conversion (rank 2, after Kyle Korver). He is currently ranked as second All Time in 3-Pointer Field Goals made, behind Ray Allen.
Notice that Kyle Korver doesn’t belong to the top 10 of attempts. - Last but not least, even if he shoots a lot from far (3 Points-Attempts around 6 times more the mean of the league), his Efficiency Rating remains to the top level, which means that his long shooting is valuable to his team. The shape of its curve follows that of LeBron James (who enters in the debate of Greatest Of All Time).
Ray Allen and Reggie Miller might have started to introduce the 3-Point game but Curry brought it to another level with crazy high numbers in attempts and in percentage conversion. He also demonstrates, visible via his “Player Efficiency Rating”, that this kind of play was possible in order to win.
More than him alone, the whole team Golden State Warriors made the 3-point Shooting as basis of their play. In fact, another shooter in the discussion is Klay Thompson who is Stephen Curry’s team player.
Together, they went to finals 5 years in a row, gaining 3 NBA championships. Even though they did not win the title in 2016, they did the best record in regular season of NBA History, 73 Victories / 9 Defeats, that people would say it has no value as the championship in the end was not won.
This philosophy of play created a dynasty and changed the way of playing from the NBA.
We can notice too that it impacts the number of SG joining the league since 2010.
In other words, as a leader from a group of players, Stephen Curry brought the Combo Guard (Point Guard / Shooting Guard) to the most important role in NBA since the last decade, as a playmaker but as a Shooter too.
Part 3. Is Michael Jordan the GOAT ?
And here it is the question that everyone would like to answer: is Michael Jordan the Greatest Of All Time?
Obviously, the answer is limited to statistics and many external factors are not considered (which have certainly a huge impact on the discussion).
First of all, I defined a simple algorithm, based on the provided statistics. The minimum of seasons considered is 8.
I considered features about:
- the value of a player to his team such as the ‘Win-Shares’ — an estimate of the number of wins contributed by a player.
- the ‘Player Efficiency Rating.
- and among other statistics factors, personal awards given to the player, added by myself to the data (only for the best players considered in the discussion by experts). It concerns the numbers of titles, the number of finals reached, the number of “best player of the regular season” and of “the finals”, …
Further info can be found here regarding the definition of the Statistics used.
From a GOAT ranking of size 10, the best player in his statistic category gets 10 points when the last one gets 1 point (ranked 10). I sum up all points attributed to the player per category and I came up with the below chart:
- it is interesting to notice that it exists a real gap between Michael Jordan / LeBron James and the rest of the top 10 players. Today, a discussion about the GOAT really exists between both of them.
- Only a selection of Statistics variables were taken in consideration. Chris Paul should not be in the top 10 of the GOAT. Even though he has no personal awards, he is known to be one of the best playmaker / game organizer of All-Time (his nickname is Point God, from Point Guard). Therefore, his contribution to the success of his team is important.
- On the contrary, Shaquille O’Neal or Kobe Bryant should be included in the top 10 (observations given by many experts).
Kobe Bryant was seen as a lonely wolf, strong but not so close to his team mates. He was taking and forcing a lot of difficult shots. On the other side, his mentality defined him as one of the most impressive and respected player. However, it could be that from statistics points of view he was not so much contributing to his team.
Surprisingly, with just considering some important factors (which remains statistics) and although basketball is not just about statistics, our ranking is somehow close to the current debate of “who is the Greatest Of All Time”.
For my personal top 3, I would go with Michael Jordan — for his exemplary effectiveness; 6 championships / 6 NBA finals, LeBron James — for his domination over 16 years in all the possible fields of Basketball, and Kareem Abdul-Jabbar — to me the best Center in NBA History and the best scorer of NBA in cumulative Points.
Conclusion
I was interested in investigating about the evolution of the NBA, in some aspects.
- I find out that the players have become more accurate that they used to be in the past.
- The long distance shot has become fundamental in the NBA. Actually, since the last generation, it is hard to “survive” in NBA if you do not develop a good shot. As the Defence has improved, it is not so easy any more to go to the basket.
- Something which was not revealed in this analysis is that the game has become faster, and often finishes with a long distance shot.
- Stephen Curry, among another list of players from his generation, introduced “officially” this new way of playing, although it was already there with players such as Ray Allen or Reggie Miller.
And I also tried to answer, from Statistics point of view, the question about the Greatest Of All Time. It came up from my simple implementation that Michael Jordan is ahead followed by LeBron James.
I leave you now making your own opinion!
For further info and to see the whole project, it is available here.
