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Dan Rosenbaum

On Friday I will attending a one-day conference at the University of Pennsylvania centered around turning pro early. This conference is mostly industry insiders from lots of sports (my panel includes a financial advisor for the the Williams sisters, a lawyer who argued the Maurice Clarrett case, and the founder of AND 1). Well, the reason I am posting this is that I think this conference may have some influence on NBA policy. (I do not know if Stern will be at this conference, but he said tonight that he will be in Philly on Friday, so he might be.)

I was wanting to hear anything that anyone here has to say about early entry into the NBA and whether an age limit would be a good idea. I would be interested in statistically based posts and non-statistically basd posts. In particular, any evidence that anyone has on how early entrants (especially high schoolers and players who left after their freshman year) have fared relative to later entrants, controlling for where in the draft a player is drafted, would be greatly appreciated.

Best wishes,
Dan

Ben F. · Joined: 07 Mar 2005 Posts: 391

Not that I'm an expert at all, nor can I do anything that advanced statistically, but I was interested in the question, so I did some investigation.

What's interesting is that although there's a strong negative correlation between # of player's under 20* in the league, and league efficiency from 94-95 to 03-04 (-.728), if you include this last year, the correlation drops to -.404. Why? Because this past year, there were 19 players in the league under age 20 yet the league efficiency jumped 3.1 points in the last year.

Why did the efficiency jump so much? It's just curious, not even related to the age limit question. In this 10 year span I'm looking at, the only other jumps over 2 points were between the years surrounding the lockout year (where the efficiency was at an incredibly low 99.2, the only time in the last 10 years it was under 100).

*NOTE: Players under 20 means players that would be under 20 at the time of the NBA draft that previous year - i.e. would not be in the NBA if the Age Limit was instituted.

Ben F. · Joined: 07 Mar 2005 Posts: 391

Dan Rosenbaum

Ben F. · Joined: 07 Mar 2005 Posts: 391

After doing some work on this, and thinking this over, I think the only person that could really effectively do this is Justin, just because he has that database with all the information you need in it. He could just query the thing for the different specific stats you need.

I don't think anyone else has the resources to effectively approach this, but I'd be interested to see the results if he decides to do it.

Anyway, here's the list I compiled of all the players in the NBA that were under 20 on the day of the draft, or would not have been in the league with the age rule instituted:

Kevin Pelton · Posted: Thu Apr 28, 2005 12:08 pm Post subject:

Dan, here's the most complete work I did looking specifically at high schoolers. I never "officially" posted it at Hoopsworld, so I doubt you've seen it:

http://www.hoopsworld.com/cgi-bin/news/exec/view.cgi?archive=39&num=8452

Mike G · Posted: Thu Apr 28, 2005 12:27 pm Post subject:

As a fan, what gripes me about the cradle-robbing is that, for example, the Pacers will grab Al Harrington and Jonathan Bender out of high school, before they are ready to contribute in the NBA -- seemingly Draft 'Em So Nobody Else Can .

This"DESNEC principle" keeps guys on NBA benches for 1-2-3-4 years, instead of allowing them to get minutes in college (or wherever), in real competition, experiencing real pressure situations, etc. Instead of developing certain character in the NCAA tournament, they travel and practice with pro players.

Using b-r.com Labs, I found 18-yr. pros (11 of 'em), and their median playing time was 224 minutes. Playing 30 MPG for 30 games (in college, say) would be 900 minutes. Call it 1000 with tournament, for a reasonable college-level year of experience.

Of 53 19-yr-olds, the median is 818 minutes in the NBA. Not too bad, but not necessarily quality minutes either.

At age 20, median is 1134 minutes. Equivalent to a major college season.

Edit: I guess these figures don't include guys who got zero minutes; so you may fudge the numbers downward.

JasonNapora · Joined: 06 Jan 2005 Posts: 6

Kevin's original column (linked to in the 'hidden' one above) has been the most persuasive for me: that drafting "second tier" high school players late in the first round is a bad economic decision since you wind up developing a guy on the bench when he's cheap & then have to pay him big bucks or watch him be good somewhere else (the Jermaine O'Neal syndrome (with the Ndudi Ebi collerary that the guy you pick may never be any good - yes I'm a bitter, bitter T-Wolves fan)). For the truly great players, I have a very hard time imagining how artificially keeping the players away from the NBA would be beneficial to their careers in the long-run (unless an age limit results in more American 18 year olds playing in Europe for two years).

An interesting study would be to take the consensus top 5 or 10 HS players from each year in the post-KG era and see if you can draw any conclusions about their pro careers based on which ones went to college & which went straight to the Association. With such a limited sample size, though, I would think any data will be awfully noisy (if LeBron, say, had spent a year making money for Ohio State it might radically shift the results).

schtevie · Joined: 18 Apr 2005 Posts: 413

Dan, you ask whether an age limit is a "good idea". To begin we should identify in whose interests a notional age limit would be. Almost certainly it is not in the interest of the highschool players. Given a likely lack of interest in schoolwork and the huge payout if drafted, it seems that we can stipulate that the real question is whether it is in the interest of the NBA to limit the age of draftees.

And what are these interests? On the one hand, it is clear that it is not fun for a franchise to eat the salary of a kid truly lacking potential. (That said, my ocular regression suggests that the kids are good for the teams and good for business.) On the other hand, if they are proposing/have a development league instead, one imagines that that doesn't make money and the NBA is thus willing to socialize the costs of player development, rather than it counting against the player cap.

Kurt · Joined: 10 Jan 2005 Posts: 30 Location: Los Angeles

Ed **Küpfer** · Joined: 30 Dec 2004 Posts: 787 Location: Toronto

It may be useful to identify the actors affected by an age limit:

* Underage players
* NBA players
* The league (owners + management + league officials)
* Everyone else (fans, media, etc)

Underage players would clearly be affected negatively by an age limit. Given the overall success of Underagers in the NBA (I did a study, somewhere) I can't see how they would benefit by being "seasoned" in college rather than in the NBA. Plus, they pick up an extra check.

NBA players themselves would benefit -- I read a recent quote from Grant Hill in which he stated that he believed the player's association had a responsibility to its present members, not to future members. It was a refreshing burst of honesty.

I'm not sure how the league would lose of gain from an age limit. I can only think that this issue is just some kind of negotiating ploy with the player's association.

If an age limit is enacted, the fans lose in an abstract sense by being denied the pleasure of watching NBA-worthy players. That is, the overall quality of the NBA players would decline, if very slightly.

I don't think I'm saying anything Dan hasn't already thought of. Just wanted to lay it out in a way that made sense to me.
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HoopStudies · Posted: Thu Apr 28, 2005 1:09 pm Post subject:

Dan Rosenbaum · Posted: Thu Apr 28, 2005 1:20 pm Post subject:

Dan Rosenbaum · Posted: Thu Apr 28, 2005 1:22 pm Post subject:

Dan Rosenbaum · Posted: Thu Apr 28, 2005 1:30 pm Post subject: