By: Melisa Li, Clarence Muchina, Leon Leibmann, Rich Chen
Since 1969, basketball games have undergone a radical evolution. A once slow-paced game is now being played at a much faster tempo as teams adopt an up-tempo and quick-paced style of play. Since its inception in the late 1970s, the three-point shot has become a much more essential component of the game, with teams now frequently relying on it as a major weapon. The three-point shot allows teams to score quickly, efficiently, and safely from long range, increasing the importance of ball control.
As more teams have adapted to this, the game became more fast-paced and exciting. But this wasn't the only change that took place. In the past, basketball positions were typically divided into five positions: point guard, shooting guard, small forward, power forward, and center. Each position had designated roles and responsibilites on the court and those who excelled in those roles were the top players in their respective positions. But after the addition of the three point line, the game has now become more perimeter-oriented. This has led to a shift in the traditional roles of players and the emergence of new positions such as the "stretch big" and "combo guard", as well as the evolution of "two-way wings". Now for those who may not know what these terms mean here's a brief overview:
A player who excels on both offense and defense and typically plays the small forward or shooting guard position. They are very crucial for teams as they impact the game both offensively and defensively. Unlike the other two positions, a two-way wing has been around for a long time, but the role has evolved over time with the effectiveness of the three point line.
In the past, wings were primarily expected to score and defend in the mid-range area, but with the introduction of the three-point line, the role has become more complex. Today's two-way wings are expected to be proficient outside shooters (ThreePoint shooters), able to create their own shots, drive to the basket, and defend multiple positions.
Some players that fit the description: LeBron James, Micheal Jordan, Kobe Bryant, Scottie Pippen, Kawhi Leonard.
The visualization above provides a clear and concise representation of the top ten points per game scorers in the NBA each year where each player is color coded by the position they play. Alongside is a shot chart that shows the location of all the shots made on the court per season. You'll notice that the positions that were the leading scorers in 1969 compared to 2022 are vastly different. This is because of the affect of the three point line that we touched on earlier in the article. Another element of the visualization is the shot chart. The shotchart is a useful tool for identifying patterns and trends in the way players score, and highlights how this has changed overtime. You'll notice that over time the shots made in the mid-range slowly starts to decline, and the shots made from the three point line start increasing. The best time period to see this change is around 2010-present. This visualization provides an engaging and informative way for people to stay up-to-date with the latest NBA stats and trends in terms of scoring over the last 50 years.
This visualization shows the evolution of the game of basketball through the three-point line. Introduced in 1979, the three-point line has now become an entrenched part of the game. We focus on the times after its introduction, the game being essentially reborn, and the three-point shot becoming a major weapon.
The visualizations in this article, support the idea of the NBA becoming more perimeter-oriented. You'll notice that in the early years of the three point line like in the 1980s and even prior to the addition of the three point line, players such as Isiah Thomas, Magic Johnson, Kareem-Abdul-Jabbar, and Michael Jordan dominated the scoring charts by scoring through the mid-range and shots in the paint. But they were not known for their three-point shooting nor their ability to stretch the floor. But with time, in the late 90's and the early 2000's, shooters like Reggie Miller and Ray Allen, paved the way for future stars on how to utilize the three point line. Then in recent years (2010's decade) players like Steph Curry, James Harden, Kevin Durant, and Damian Lillard have dominated the scoring charts, and they have done so by relying heavily on their three-point shooting. And players who weren't great three point shooters early in their careers like LeBron James have improved their three point shooting signifcantly in order to keep up with the now three point dominated league. There is not a single top scorer in today's NBA that isn't an effective three point shooter, which goes to show how the three point line has revolutionized basketball.
Note the presence of anomalies in the data. Years such as 1998 and 2011 saw lockdowns due to NBA players forming a major strike. 2020 was an additional year of turmoil due to the COVID Pandemic. These impacts are apparent and significant. Another thing to consider is that shot chart data was not recorded until 1996, but even then it was still very limited, the data is most accurate in the 2000's. This is because the advanced tools needed to record this data had not yet been developed at the time.
In 1998 Players and owners had a dispute on revenue sharing and players' salaries, with the CBA just expiring, Owners wanted to renegotiate terms that would favor them and provide them with more control over players, but of course, the players weren't having it. This caused the players to go on strike for about 200 days, which resulted in them missing games and losing millions of dollars, but with the NBA losing billions. This shortened the upcoming NBA season and created an anomaly in our dataset.
In 2011 the players and owners had another dispute regarding the main issues that were prevalent in 1998, with revenue sharing and player salaries being the key sticking points. The NBA's collective bargaining agreement (CBA) had again expired, and the owners wanted to renegotiate the terms of the agreement to address what they saw as an imbalance in league revenues and player salaries. And again the players didn't agree, and to deny any further advances owners could make they went into another lockout (strike) and this resulted in the players and the NBA losing tons of money, until the owners and NBA gave into their demands, but by then almost half the season had proceeded. Thus, there was a much lower number of games that season.
In 2020, there was a COVID pandemic that put the whole world into lockdown, not just the NBA and their players this time. This resulted in many missed games, and therefore, another anomaly in our dataset.
Basketball is an all-around loved sport, with entertainment such as the National Basketball Association (NBA). With so many fans of the sport, one could wonder, how has the NBA league changed over the years? That is why our group chose to base our interactive visualizations on different performances per season using the data provided by the official NBA site
The end goal of these visualizations, broadly, was to show and analyze a key trend in basketball. In the relatively short span of just over four decades since the introduction of the three-point line, the world has witnessed a dramatic increase in the number of three-point shots played per game. Our combined visualizations, therefore, were built to communicate this trend.
The design of the racing bar chart was created with the idea of a coherent, pleasant to view, and engaging visualization in mind. We designed it to communicate very clearly who the top ten scorers were each year, as well as their positions, and on average how many points each scorer scored per game. To ensure effectiveness, we prioritized encoding the most important data with length and position, with length encoding the quantity of shots that player scored, and position encoding that player's ranking.
The animation that allows years to play out chronologically helps to enforce a notion of the passage of time to the user. The user can still choose specific years, but the animation will allow the data to just speak for itself and play out, allowing the very notion of passing time to also communicate that dimension of the data - after all, what better way to encode time than time itself?
The use of color was also very important. We wanted to make something that would be as accessible as possible to a wide range of people. To that end, we embarked upon a search for effective color schemas. Eventually, we settled on the commonly used Okabe-Ito palette (designed by Masataka Okabe of Jikei Medical School and Kei Ito of the University of Tokyo), drawing upon five of the palette's eight colors. We ran several tests to verify the distinctiveness of these colors using such tools as Coblis (color blindness simulator) to simulate the perceptive ranges across a variety of views, including protanopia, deuteranopia, tritanopia, and achromatopsia. This way, it was readily apparently to anyone exactly what role various players were, and thus the target audience could experience exactly how various roles have become more/less important as a scoring role.
The neighboring heatmap was encoded with positional data to provide an alternative perspective on the locations where shots were taken and with regards to which ones were successfully landed or missed. This allows for a multi-dimensional understanding of where shots are actually coming from, and to fans of the sport, they will readily be able to imagine what that might actually correspond to in actual games.
Finally, we also included a fairly simple line chart to show the increase in average three-point shots per game compared to the decreases in two-point and free throw shots. These trends support the rest of the article and visualizations, and show how the three-point shot has quickly become a staple of the game, carving out a position for itself resulting in slightly less emphasis on two-point and free throw shots. We use a difference in color to communicate the three different kinds of shots, to ensure there is no confusion about which shot is currently being displayed, along with an interactive drop-down menu that allows the user to explore these types of data.