The 2015-2016 NBA playoffs have just begun meaning 16 fortunate teams are still playing ball while 14 others are preparing for the 2016 Draft and beginning to set up the structure of their team for next season (“There’s always next season”).
The concept of drafting players is an interesting one. So much goes into it – athleticism, physical stature, game smarts, college performance, and the player’s mentality (IE, will they be able to handle the pressure, will they fit in with the guys and have good team chemistry, etc). Recently, Motomura and colleagues (2016) discussed the role the draft can playing in building an NBA franchise. More importantly, they set out to understand whether having more or higher draft picks actually made an NBA team better. They concluded,
“We find that the draft is not necessarily the best road to success. An excellent organization and General Manager better enable teams to succeed even without high draft picks.”
This got me thinking – could we potentially try and understand which teams are “excellent” organizations in terms of selecting players that enjoy success at in the NBA? Additionally, I am really interested in the Philadelphia 76ers. Year after year they always seem to be in the conversation of tanking at the end of the season, in order to increase their chances of obtaining higher round draft picks in the NBA Draft Lottery. In fact, they have been so good at this over the past few seasons that the 2016 season is supposed to the final season of the tanking era in Philadelphia. Unfortunately, their efforts to tank and stock pile great players has not payed off. They seem to have a hard time either:
- Selecting good players. If you are going to tank you better not miss on your draft picks!
- Developing players or bringing in veteran players who can surround the young stars so that they don’t have to play a high number of minutes their rookie season and carry the team (something also addressed in the Motomura above).
The Data
2011 – 2015 NBA Draft data was obtained from basketball-reference.com.
Aims
- With 60 picks in the NBA Draft (300 total over the 5 year period) how many players, on average, do teams pick up?
- What is the average value of players selected in each of the draft number spots?
- Which teams have been most successful at picking players that added a high amount of value to their team?
- What is going on in Philly?
Number of Draft Picks
Over the 2011 – 2015 NBA Draft 300 total players have been chosen, with teams averaging 9 players drafted during that period. The 76ers certainly are leading the way, selecting 21 players over this 5 year stretch. (NOTE: You will notice there are 34 teams in the table below. This is because I left in expansion teams and teams that moved from one city to another during this 5 year period. I did this to just represent what took place in the draft between 2011 – 2015).
What is the value of a draft pick?
Value or Success metrics are often one of the more difficult things to pin down when studying team sport athletes. Lots of things players do can add value to a team without ever making it into the box score (which primarily consists of count metrics). The writers at basketball-references.com display two metrics which I used to quantify a player’s value – Win Shares and Value Over Replacement Player. Both of these metrics are the type of metrics that were born out of Baseball’s Sabermetrics as a way of trying to provide more context to the box score metrics presented to fans everyday on websites or in newspapers. Win Shares is a metric that takes the teams success and divides up credit for that success among the participating players. Value Over a Replacement Player is a metric which projects the player’s value versus a fictitious replacement player. Both of these metrics have limitations and people argue frequently over which is more useful or whether we should use a different metric to represent value (E.g., Player Efficiency Rating or something like +/- or Adjusted +/-. Both of which have their own limitations). I simply chose these metrics because they were readily available and they would provide me with a quick way to represent player value. Any metric one deems important would suffice, though.
To reflect value per pick I summarized the data in a few ways:
- I binned the picks into groups of ten (Picks 1-10, 11-20, 21-30, 31-40, 41-50, and 51-60). Because I was dealing with a five year period it meant that there would only be 5 picks for each selection (1-60), which wouldn’t provide enough data. Thus, binning it this way helped me group more players together.
- Since I am using 5 years of data it isn’t really fair to look at something like Win Shares for all of the players, since players who were drafted in 2011 have a much longer time to contribute to their win share compared to a player drafted in 2015 (a rookie). Thus, I reflected Win Shares over Games Played, to attempt to look at each player’s contribution to their teams success relative to the amount of games they participated in.
- Finally, I added in Minutes Per Game, simply because I wanted to see what the participation differences were between the bins of draft picks.
The data in the below table is the average of each metric for the six different draft pick bins.
As we would expect (or should expect) there is a monotonic decrease in each of the three metrics as we move from Pick 1-10 to Pick 51-60. This is to be expected and tells us that the quality of player begins to decrease as we move down the draft board (better players are being selected higher up). The only place this doesn’t seem to happen is in Pick 41-50 for the Average Value Over Replacement Player. I’m not really certain why this is. It could be that during this five year stretch there were a lot of players selected from those picks that had minimal to no contribution to their team.
Draft Pick Value Per Team
First, we look at the sum of Win Shares Per Game for each draft pick bin. I added up the win shares per game for each player the team selected in each of the draft pick bins and then summed those up to obtain a 5 year “Value Add”. I then standardized the scores in order to see how each team did relative to the average Value Add during this 5 year stretch.
NOTE: There is a limitation with this analysis in that I didn’t have a way of going through each player to see if they played for their draft team over the entire 5 year period. It is entirely possible that some players moved on or maybe got drafted and immediately traded and never had a chance to play with their draft team (as we will see when we discuss Philadelphia). That being said, what quickly jumps out is that 6 teams appear to be very good at identifying those who will be valuable NBA players, whether they still play on their draft team or not – Houston, Cleveland, Detroit, Denver, Minnesota, and Utah. It is important to keep in mind, however, that some of these scores might be coming from one or two players during this five year period. For example, guys like Karl-Anthony Towns (Minnesota) and Kyrie Irving (Cleveland) make significant contributions to their teams in terms of Value Add. Both players were also #1 draft picks.
Another interesting observation is the value Houston, Cleveland, and Detroit were able to find in Picks 31-40. Those three teams stand alone in that draft pick bin as all of the other teams seem to lack the ability to find valuable players. Houston looks to be pretty incredible at identifying talented players as they are green in several of the draft bins and have had the most success in drafting (using Wins Shares as the metric of success) compared to other teams over this period. Houston also happens to be a team that is praised for their analytic savviness and perhaps this helps contribute to their ability to scout talent.
In looking at this chart, Philadelphia doesn’t appear to be doing too bad (7th ranked team). However, it is important to keep in mind the limitation of this chart in that some players might be adding value for teams other than the team which drafted them. I do give Philly credit for identifying some of the players as potentially successful players but trading them away doesn’t help. This will be discussed later in the article.
Next, we turn our attention to the Value Over Replacement Metric. For this analysis I took the average Value Over Replacement for each of the draft pick bins for each team. I then took the average of every draft pick bin for each team and created a 5 Year Average Value Over Replacement Player. This metric was then standardized for all teams to investigate how they did relative to the rest of the league.
Now we get a little bit of a different look at the league and how successful teams draft players. As in the above analysis, there is a similar limitation in that players may have moved on from the team that drafted them; however, the main goal is to understand who is good at identifying talent.
We still see Houston in the top 6. Not only are they selecting players that are adding win value but these players are also contributing more than the replacement player would. Golden State, who was in the top 10 on the previous chart, looks to steal the show here with players above the replacement level player. Philadelphia takes a bit of a hit in this chart.
So What is Going on in Philly?
This is a tough one to sort out. As I alluded to above, sometimes teams draft players and then move those players on to other teams. Philly has been accused of tanking in order to get better draft picks and if you are going to try and go out of your way to get better draft picks then you need to ensure those draft picks actually turn into great players. Otherwise, you just end up being in the same position next year. Philly drafted 21 players over the past 5 years – well above the norm for an NBA team during this time.
- Of the 21 players drafted only 7 of those players actually ended up playing for the team in some capacity.
- Of those 7 players, only 4 of them remain with the team.
- Of those 4 players, one is Joel Embiid, who has not played a game in his first 2 seasons with the team due to injury. Embiid was the 3rd round pick in the 2014 draft and has proven, thus far, to be a very costly selection for the franchise.
Here is an overview of the 21 players Philly has selected in the past 5 years:
Conclusion
Drafting players is really difficult. There are a lot of things that go into it and some may say it is a lot of luck. That being said, there are some teams that seem to come out on top or near the top, year-after-year. You can have those big luck years where you snag a lot of great talent and hit a home run but I think more importantly you just need to be consistent. The big luck years are good but the years where you are consistently bad end up setting you back. As discussed in the Motomura paper, having a well run organization that understands how to not only develop talent but also bring in veteran players to surround the younger players and take some of the pressure off might be the most important thing. Too often I think teams try and tank with the idea that their first round pick is going to save the franchise next season. Instead, they should consider the things they need to do to help that first round pick develop into the player they need him to be, down the road, in order to save the franchise.
References
from Optimum Sports Performance LLC http://optimumsportsperformance.com/blog/2016-nba-draft-how-do-you-put-together-a-team/
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