Computers vs. Scouts, Updated

Erich Doerr and John Hollinger have each published new analyses, looking at the 2008 draft from a purely statistical standpoint.  Doerr’s piece at DraftExpress nicely summarizes some of his previous work, for a new audience.  He’s extremely cautious. The article is not, strictly speaking, a ranking system. Doerr uses his ratings to give essentially a thumbs up/thumbs down (or at least a caution) for each of the high-profile players. 

Of note: Don’t get too excited about any of the guards… don’t sleep on Mareese Speights. 

Hollinger, unlike Doerr, thinks he has it nailed.  He’s also totally revamped his method since last year. He’s now done – he says – a regression analysis, rather than an ad-hoc mix-and-match method. He’s devised two different systems, one for bigs and one for other players. Today he writes about the Big Men (Insider is free this week). For bigs,

    “The formula considers 16 variables: height, age, schedule strength, team strength, and the usual individual stats (assist ratio, turnover ratio, usage rate, pure point rating, defensive rebound rate, FTA/FGA, 3A/FGA, PER, blocks per minute, steals per minute, field-goal percentage and 3-point percentage). Note that two variables — offensive rebound rate and free-throw percentage — didn’t make the cut as they were found to be almost completely irrelevant in determining pro success for big men. Also, testing showed that looking at multiple seasons improved accuracy quite a bit. As a result, all of a player’s seasons count on his record.”

Of note: Michael Beasley rates as the best big-man prospect since he started calculating in 2002. (Personally, I think there’s a good chance anyone taking Rose at #1 feels silly in a few years)… Mama Lopez will be disappointed…. Mareese Speights looks good here, too…. and Anthony Randolph — wow. I think this might be a little harsh, since he’s so young and so skinny he has a lot of room for improvement, but this is as damning a projection as you can find.

And here’s the smackdown: Hollinger’s numbers suggest that Joey Dorsey will struggle to have an NBA career at all. Doerr thinks Dorsey looks like a big-time player. 

Computers vs. Scouts

With 16 days left before the draft, teams are busily working out prospects, haggling with agents and breaking down game tape. Could there be an easier way? Last week we were talking about computer rating systems that purport to identify the best draft prospects, without the messy work of actually watching games, administering brain profile tests and trekking through rundown former Soviet airports.  The two systems that have garnered the most attention were designed by Erich Doerr, a David Berri disciple, and ESPN’s John Hollinger. A good summation and explanation of the systems was posted here last year:

 http://www.knickerblogger.net/index.php/2007/06/26/draft-analysis-by-the-numbers/

The short version: Doerr’s “PAWS” (Pace-Adjusted Win Score) rating looks solely at college game statistics, ranking players using Berri’s winscore metric. He adjusts for strength of schedule (40 points against Kansas means more than 40 points against Helen Keller). Doerr’s posts are not easy reading, but it appears he simply takes the best-ranked players and assumes that those are the best NBA prospects.  

Hollinger starts with a similar approach, using his PER (Player Efficiency Rating), calculated with college game statistics.  Unlike Doerr, he makes a number of adjustments.  In essence, this puts Hollinger closer to mainstream draft gurus. He finds that players who are tall for their position tend to do better in the pros. He also finds that certain statistics – like steals – are specific markers of athleticism. Unlike Doerr, Hollinger also takes age into account. An 18-year-old prospect with the same numbers as a 22-year-old prospect (or even a 19-year-old) gets a significantly higher rating.

Even the creators of these systems would say that they are only a tool, and very much a work-in-progress.  A smart drafter might use them to identify promising players to whom he or she hadn’t paid much attention, or to raise red flags about prominent players who might be overrated.  Here’s a comparison of what the Hollinger & Doerr computers spit out last year, along with the actual draft order.  Since both systems rate only college players, for the sake of side-by-side comparison I left Yi Jianlan and Marco Belinelli off the actual draft list.  That’s right, these methods won’t tell you who’s tearing up the Italian League, or whether OJ Mayo’s high school career was more impressive than that of LeBron James.

Oh, and Nick Fazekas? He only played 269 minutes as a rookie, but per 40 minutes he scored 15.9 points and had 13.2 rebounds, along with a TS% of 58.2 and a rebound rate better than David Lee or Zach Randolph.

     Hollinger                                           Doerr                              Actual 2007 Draft

1. Kevin Durant                                  Nick Fazekas                       Greg Oden

2. Greg Oden                                     Kevin Durant                        Kevin Durant         

3. Mike Conley, Jr.                             Al Horford                            Al Horford

4. Thaddeus Young                           Greg Oden                            Mike Conley, Jr.

5. Brandan Wright                             Joakim Noah                          Jeff Green

6. Al Horford                                     Jared Dudley                         Corey Brewer

7. Nick Fazekas                                 Jason Smith                           Brandan Wright

8. Josh McRoberts                             Morris Almond                       Joakim Noah

9. Rodney Stuckey                             Julian Wright                         Spencer Hawes

10. Jared Dudley                                Brandan Wright                     Acie Law, IV

11. Joakim Noah                                Rodney Stuckey                    Thaddeus Young

12. Glen Davis                                   Al Thornton                           Julian Wright

13. Sean Williams                               Mike Conley, Jr.                    Al Thornton

14. Jeff Green                                     Glen Davis                            Rodney Stuckey

15. Kyle Visser                                   Daequan Cook                      Nick Young

16. Herbert Hill                                  Marcus Williams                    Sean Williams

17. Javaris Crittenden                         Jeff Green                             Javaris Crittendon

18. Wilson Chandler                            Sean Williams                      Jason Smith

19. Julian Wright                                 Corey Brewer                        Daequan Cook

20. Daquean Cook                              Derrick Byars                        Jared Dudley