by Stanley Dai
Every year, hundreds of basketball players with hoop dreams enter into spectacles known as the NBA draft and free agency, where teams select players based on their own needs and evaluation of these players’ talent.
As a fan of one of the more woe-begotten franchises, the New Orleans Pelicans, I was pleasantly surprised to see three rookies make meaningful contributions to team success. Uniquely, all three rookies were former college upperclassmen, lauded for their maturity and poise.
There are many approaches to incorporating new talent, with various and often conflicting theories bandied about by NBA pundits and internet forums. One such adage is that older players are often more ready to make an immediate impact.
To explore this proposition, I use data on rookies and teams from basketball-reference.com from 2014-2021. I select this time period mostly out of convenience - certain teams had different names prior to 2014. Further documentation can be found on my GitHub.
For my purposes, contribution is measured as having played in at least 35% of all games, the statistical minimum for rookies to qualify for historic recognition by the NBA. Winning teams are defined as teams who win more than half of their games.
The chart above describes the number of rookies who contributed to their respective teams over the last eight years. 85% of contributing rookies are 23 years old or younger, many of whom were drafted out of college.
For nearly all ages, more rookies play for losing teams than winning teams, which makes some sense - teams out of the championship race are incentivized to bring in more new talent and give players more chances to develop.
Furthermore, it appears that contributing rookies under 21 are less likely than their older counterparts to be on winning teams.
Let’s explore another dimension of the same question - what is the magnitude of the contribution of rookies on winning teams? As a proxy for level of contribution, I use minutes played per-game.
While older rookies are more likely to be contributors on winning teams, on those same winning teams the median minutes-per-game generally decreases with age! My best, most irresponsible guess as to what might be going on here is that younger players must exhibit extraordinary talent in order catch the eye of good teams. In other words, if you are a contending team taking a chance on a 19 year old, he better be pretty damn good.
As team-building strategy is predicated on a near infinite amount of confounding factors, analysis provided can only be descriptive in nature. Future analysis could explore a longer time frame or look solely at drafted rookies.