One of the stories told in Stumbling on Wins is that draft position is a poor predictor of an NBA player’s future per-minute productivity. A player’s college numbers are a better predictor, although the link between college and pro performance is not nearly as good as we would like.
Up until a few weeks ago, though, all we had were those college numbers. But with the preseason now complete, we now have more numbers (thanks to Doug Steele) to use in our evaluation of rookies.
Back in 2008, a model was offered connecting a player’s regular season per-minute Win Score (WSMIN) to his per-minute Win Score in college and the preseason. This model has now been updated. Utilizing 80 observations from 2007, 2008, and 2009; the aforementioned model was re-estimated. The results indicate that 61% of a rookie’s regular season WSMIN is explained by what he did in his last year in college and the prior preseason. This isn’t perfect. But the explanatory power is better than what you see if you consider college and preseason performance alone.
And what do you see when you look at both college and preseason performance? There were 19 rookies who played college basketball and at least 100 minutes in the past preseason (at least, I was able to find data on 19 rookies). The following table presented what these rookies did and then uses this information to predict WSMIN and WP48 [Wins Produced per 48 minutes] for the 2010-11 season [as noted in the past, one can use WSMIN to project WP48].
And here is what we learn from this analysis:
- Blake Griffin appears to be very good. The model predicts his WP48 will be 0.279. Since 1977-78, only twenty players 21 years old or younger have posted WP48 marks equal to or better than 0.279. And the names on the list put Giffin in very good company. As the following table illustrates, if Griffin’s production matches this prediction he will join a list that includes Magic Johnson (listed twice), Shaquille O’Neal (listed twice), Michael Jordan, Chris Paul, Tim Duncan, LeBron James, Kevin Durant, and Dwight Howard. In sum, the Clippers appear to have found a star.
- After Griffin, the next best rookie – among rookies taken in the first round — is Evan Turner. Last season Tyreke Evans was named Rookie of the Year and posted a 0.159 WP48. Such production led all first round draft picks last year (although DeJuan Blair – as second round pick in 2009 – posted a higher mark). Turner projects to be somewhat more productive than Evans, so that will give fans of the Sixers something to watch (on a team that might not have much else to be excited about).
- As good as Evan Turner might be, Landry Field and Jeremy Evans might be even more productive. Both of these players, though, were taken in the second round. And given the link between draft position and minutes played (those taken later play less), it is possible neither will play enough to make much of a difference for their respective teams.
- That will not be the story for John Wall. Wall will definitely get minutes. And because John Wall will probably score, he will receive consideration for Rookie of the Year (although Griffin scored more per game in the preseason). But Wall has yet to post outstanding numbers. He didn’t do it in college last year; and he didn’t do it in the preseason. Now does this mean Wall will never be great? NO (as I have said before). It does mean, though, that Wall has yet to be great. And I think it is unlikely (although certainly possible) that Wall will be “great” his rookie season (although Wall might become a “great” player later in his career).
- Around the draft there was some debate concerning Wall and DeMarcus Cousins. The former was considered the better player. The latter had better college numbers. When we look at college and preseason, though, Wall and Cousins are not much different [with Wall having a slightly higher projected WP48]. So maybe the Wizards were wise to pass on Cousins. Passing on Turner, though, may not have been the right call.
- Finally, we have the last name on the list. Derrick Favors was offered to the Denver Nuggets for Carmelo Anthony. So far it looks like the Nuggets were wise to pass on that offer. Sure, Melo is overrated. But he does offer something. So far Favors… well, he didn’t offer much these past few weeks.
Again, we need to emphasize that these are only projections. And all that is being projected is the first season. Back in 2007, Kevin Durant’s rookie season was projected with these two data points. That projection indicted that Durant would struggle as a rookie. Although Durant did not play well as a rookie (so the projection was correct in Durant’s case), he ultimately did get much, much better. A similar story could play out for any of these players (then again, it might not).
All we can see is that using data from college and the preseason does tell us more than we knew with just data from the NCAA. But these two data sets don’t tell us everything (and in a few days, we will start to see what we haven’t seen so far).