Pelton's WARP Projections

[r_u_s_t_b_u_c_k_e_t]

Are you Pelton?
Let me tell you what you should do. You should test your theories. Go back over the past 10 years of the draft. It's easy to google college and pro stats. Show the actual production for the 1st round picks compared to what your WARP(ed) method would have predicted. It's called the scientific method. If you want to have a system used and accepted by NBA execs and fans, you have to show it works within a reliable range. This article show it's pretty awful. But yes, if you can't make the data match your already determined theory, then rely on the "give it time" excuse.

Since you asked... I'm not Pelton.

Here's the breakdown you ask for (sorry, it is Insider):

https://insider.espn.go.com/nba/draft2013/story/_/page/PerDiem-130625/how-warp-projections-fared

If you can't read it, he has included every draft back to 2006.

He addresses the topics of translating stats, both from the NCAA and Europe, and how they've gathered enough stats over the years and mapped them to success in the NBA so they know better where to look for markers of later success in the NBA.

He also gives examples of where his projections were way ahead of the team's actual picks. I believe that Forbes writer asked for those.

2012: Rivers, Leonard
2011: Jimmer, Parsons
2010: Turner, Wesley Johnson
2009: Curry, Taj Gibson
2008: Ryan Anderson, Chalmers
2007: Stuckey, Law
2006: Millsap, Morrison

The Forbes writer even mentions Curry and Stuckey, even though they slipped. Pelton had Millsap as the 2nd best player in the 2006 draft.

 

[franklin]

Why? Because it doesn't mirror the groupthink mock drafts? How is it that so many drafted players bust, and yet every single mock draft is so similar?

For starters, it's nearly impossible to incorporate college stats into any model because the competition database is so vast and team play is so variable within season that it's virtually impossible to adjust for strength of opponent like the statisticians now do for major sports.

This is good? All the guy does is throw out a few examples of bad projections from the past couple of drafts, and even some of those are hardly bad (mocking Drummond at 5?). And Pelton's projections are supposed to be over 5 seasons, so there is still plenty of time for his guys to turn it around.

Where are all the examples of the team's draft busts?

Draft busts is a strawman here. Everyone knows drafting is an imprecise art. Go ahead and set that one up to burn down if you must, but it doesn't have any bearing on the validity of pre-draft analytical models.

 

[r_u_s_t_b_u_c_k_e_t]

It's called the scientific method.

What is the scientific method used in the mock drafts that you prefer?

 

[r_u_s_t_b_u_c_k_e_t]

For starters, it's nearly impossible to incorporate college stats into any model because the competition database is so vast and team play is so variable within season that it's virtually impossible to adjust for strength of opponent like the statisticians now do for major sports.

Pelton is attempting to do it. See the link above.

Draft busts is a strawman here. Everyone knows drafting is an imprecise art. Go ahead and set that one up to burn down if you must, but it doesn't have any bearing on the validity of pre-draft analytical models.

Your Forbes guy set up the strawman argument, not me. I was just pointing out his hypocrisy in doing so.

 

[Coach Ellis]

Forbes put out a good column covering Pelton's WARP, among other pre-draft analyticals.

https://www.forbes.com/sites/markhe...s-marcus-smart-isnt-best-player-in-nba-draft/

This is a great article. Thanks for sharing. Repped.

 

[mct]

I always love the reaction from people when confronted with these kind of predictive models. Of course they go against convention. What would be the point of them if they just confirmed the hype for every prospect?

Production-based variables, even with the noise of very different competition, are still the most powerful tool when trying to predict a player's future. They miss a lot of things, sure--how can you account for the situation a player is drafted into, for instance?--but, assuming Kevin Pelton has done good work, his big board is definitely a more accurate representation of reality than the lists you have in your heads after reading hundreds of mock drafts and scouting reports and media bull****.

Some ESPN dudes were saying today that this draft is 22 deep. It makes my head hurt--nay, my soul weep--to read something so stupid.

 

[mct]

To be clear, I'm not advocating blindly following a model like this one when making your draft choice. I would still draft Wiggins first because I believe a lot of the stories that explain his mediocre production.

But if you did blindly follow the model year after year, you'd have more quality players on your roster than had you just stuck with the gut feelings of some pro scout.

 

[r_u_s_t_b_u_c_k_e_t]

Here's is some of the explanation about how he translates stats:

I've been working on college stat translations for a decade now, and they've appeared as projections in the "Pro Basketball Prospectus" annuals. In theory, the method is simple. I take 14 statistical categories that sum up the box score, all of them pace-adjusted, and look at how much players drop off between the NCAA and the NBA. Players tend to see the biggest drop in their block rate (down by more than half), while they actually commit fewer turnovers at the NBA level because they tend to handle the ball less frequently.

There's one important additional layer, and that's accounting for strength of schedule (measured by KenPom.com's SOS) to ensure that players from small colleges aren't overrated. Schedule has historically been most important for translating usage rate and free throw rate, two places where players from small schools see much bigger declines than their major-conference counterparts. A smaller adjustment is applied to all other stats.

 

[r_u_s_t_b_u_c_k_e_t]

Pelton also writes about the "lingering value of potential", how players' prep rankings follow them all the way to the NBA draft.

In general, prep recruiting rankings explain about half as much of the variation in where players are picked as their WARP projections (based on college performance and age), despite the fact they add nothing to the projections when determining a player's actual value (measured by WARP) in the NBA.

Said more plainly, teams put too much value on how prospects rated entering college. It's too early to tell whether Barnes, Muhammad and Rivers will be good draft picks, but so far they have performed in the NBA much like they did in college.

 

[Jazz4ever]

The college game is just a totally different animal than the NBA game. Some players have college 3 point range but not NBA (Derrick Williams). NBA spacing helps some players more than others and there is no way to predict it. The overall sample size of games is tiny especially for a one year player. I think the vanilla RSB/40 probably does a better job.

 

[Stifle Tower]

What is the scientific method used in the mock drafts that you prefer?

Scientific method would be taking the mocks and seeing how closely they correlate to actual player performances. Seat of the pants here, but I'd say they're probably as accurate as Pelton. However, instead of the mocks, which are put together by writers, you'd need to get actual draft boards. These are put together by teh scouts and GM's who watch countless hours of film and attend hundreds of games.

 

[r_u_s_t_b_u_c_k_e_t]

Scientific method would be taking the mocks and seeing how closely they correlate to actual player performances.

This is exactly what Pelton is doing. He runs his WARP projections for old drafts. Then he compares those to the way the players actually performed in the NBA and attempts to adjust his formula to make it more accurate going forward.