Measuring the Utility of Player Movements
There are continuous player movements in NBA from the end of a season to the next season’s trade deadline (generally at late February), because trades and free agents signings are important pieces of improving teams’ performance.
In 2013-14, there were 43 players who played for two different NBA teams, and there were 2 more who wore three NBA teams’ jerseys in that season. In 2014-15, these numbers were even higher. 58 players stepped out for two teams and 7 players played for three different teams. But as expected, inner-season player movements are relatively few comparing to the off-season moves. There were total of 126 players who had finished the 2013-14 season with a different team than they opened in 2014-15 season.
Thinking there are approximately total of 450 different players in each of NBA season, we can roughly say that more than 25% of players change teams in the off-season, and more than 10% of players change teams in the regular season. This is an intense traffic. In this analysis, we will try to answer the question of which players movements are well-done and which others are not.
To do this, the key factor is the measuring players’ performance for their teams and establishing a valid comparison metric.
- We selected the players who had changed teams in 2013-14, in 2014-15 or between.
- Firstly, we did not consider financial concerns of player movements and only compared players’ contributions in the games.
- We compared players according to their overall performance based on their in-game basic stats (their efficiency score) calculated using seasonal total player stats with this formula: PTS+(FGM-FGA)+(FTM-FTA)+REB+AST+STL+BLK-TO. Then, we found the average of each player’s efficiency score per game played and per minute played.
- In order to select the right payer cluster, we filtered out players who played less than 15 games or less than 20 minutes per game.
- Finally, we compared the efficiency score of players in their previous teams and then in their next teams and calculated the gap between them.
- After normalizing the scores of efficiency per game, efficiency per minute and efficiency improvement (difference of performance in the previous and next team); we took the average of these three.
- This metric gives us the comparison value of if this player movement is successful for the new team or not.
Best Player Movements after the start of 2013-14 Season
The following table shows us the best trades/free agent signings of the last season according to their efficiency contribution of to their new teams.
On top of the list, we see Enes Kanter of Oklahoma City Thunder. Although many critics for his defensive capabilities, he played surprisingly well in the last 28 games with Thunder. In fact, in per minute stats, he is the leader of all players in efficiency score and he increased this 0.2 points in OKC comparing to the Utah Jazz.
Pau Gasol is the second best FA signing of 2014-15. He’s clearly rejuvenated in the Bulls jersey last season with the massive average of 18.5 ppg, 11.8 rpg, 2.7 apg, 1.9 bpg and 0.494 FG%.
In this list, there are two unexpected names: Alexey Shved and D.J. Augustin (from 2013-14 Bulls season). Both players performed averagely considering efficiency per game and per minute stats but their performance have increased enormously comparing to their last teams (0.32 and 0.33 per minute). They obviously came from nowhere.
And at the 7th place, we see LeBron James. Actually, he is one of the top performer of 2014-15. But his 2013-14 season with Miami Heat was so legendary that his season with CLE seems like a decline comparatively. This is why he found himself at that place.
Most Unsuccessful Player Movements after the start of 2013-14 Season
Let’s also see the unproductive player movements where player contributions are almost disappointing for their new teams. On the first place, we see Brandon Knight. In fact, he was having fantastic season with Milwaukee Bucks before traded to the Phoenix Suns where his production dropped 0.23 efficiency score per minute. Arron Afflalo was almost a star in Orlando Magic, but his contribution the Portland Trail Blazers was nowhere near. At the 5th place, there is Lance Stephenson who was one of the last season’s most unsuccessful free agent signing.