Baseball Prospectus launches DRC+

On Monday, Baseball Prospectus unveiled their latest advanced stat, Deserve Runs Created Plus. Jonathan Judge, one of the inventors of the stat and now one of the new proprietors of Baseball Prospectus, teased this new stat at the latest Saberseminar in August. It definitely piqued my interest, and I was excited for when BP would officially role it out.

I have been a big fan of wRC+ for years. It is adjusted for league effects, park effects, and the scoring environment, so you can use it to compare players across eras. It is easy for anyone to understand. But of course, as with all stats, it had its shortcomings. It did not adjust for quality of competition. The standard deviation for it is never given, i.e. how different do two separate wRC+ values have to be in order for it to be significant? It does not tell us how much of the player’s skill went into that value. The park adjustments assume that players play all their games at home. This is not a problem when dealing with parks that are neutral or close to it, but it becomes one when going to the extremes.

I have heard Rockies writers gripe how wRC+ over-corrects their hitters. DRC+ does a much better job of handling park factors. Todd Helton has a career 132 wRC+ but a 146 DRC+. Nolan Arenado has a career 118 wRC+ but a 137 DRC+. This is just one way that DRC+ improves upon wRC+. When a new stat comes out, it is fun to see if there are any major changes to how we view some players. The aforementioned Todd Helton is a great example. He is a borderline Hall of Famer, but his DRC+ helps him a lot.

It is my understanding that BP is going to unveil more in the coming weeks on how DRC+ was developed and calculated, or at least as much as they can. Like with DRA, they can’t give away exactly how it is calculated for proprietary reasons. Even if they could, I am not qualified to peer review it. Just remember that complexity by itself is fallacious reasoning to reject a model. So far, I am a fan of DRC+, and I expect to use it in the future, but I have a couple of reservations. For now I will keep them to myself until I learn more.

BP’s Matthew Trueblood decided to revisit the Trout/Cabrera MVP argument from 2012 and 2013 because DRC+ changes things. He did something similar when DRA came out by seeing how much it affected how we look at the career of Jack Morris.

The last thing I want is to revisit the Trout/Cabrera debate, but I read the article anyway. It was definitely interesting. It was fascinating to see how it affected their offensive evaluations, specifically Trout’s. DRC+ widens the offensive gap between those two. That resulted in Trout’s WARP, BP’s version of WAR, being equal to Cabrera’s in 2013 and one win behind him in 2012.

Trueblood deserves a ton of credit for admitting to his belief of being wrong, but I don’t believe he was. There are two problems with claiming to be wrong here, one being that the argument I presented in the above paragraph has problems with it. It only measures one of the three versions of WAR. WARP now uses Deserved Runs Above Average (DRAA), so let’s see what happens when we replace the offensive components of fWAR and bWAR with DRAA.

Trout still comes out on top everywhere except 2013 bWAR, and a 0.1 difference is negligible. Furthermore, DRS hated Trout’s defense in 2013, which seemed excessively so. Of course, nobody should be comparing players based solely on their WAR values. The crux of the argument for Trout was always that he was a center fielder whose defense and baserunning made up for Cabrera’s superior offense but terrible defense and baserunning. I don’t believe that has changed even with the hit Trout’s offense takes in DRC+. I think the best we can say was that voting for Cabrera in 2013 MVP was more defensible than we thought. I hope to never discuss this debate again.

Even if DRC+ could conclusively prove that Cabrera unarguably deserved those MVP awards, that does not make Trueblood or anybody else who argued for Trout before “wrong.” It was the best, most logical conclusion based on the evidence available at the time. When writers were handing out MVP awards decades ago based on RBI, they were not “wrong” either. They did the best they could based on what was known at the time. When science improves upon preexisting knowledge, that does not necessarily mean that what was known previously was “wrong.” If something comes out that is even better than DRC+, that does not mean that DRC+ was “wrong” either.

This is how science works! I am reminded of Asimov’s Axiom, which states that science is cumulative and progressive. DRC+ is built on what came before it. In one of the DRC+ articles, Jonathan Judge himself states that DRC+ is an attempt get things more right, and not that what came before was “wrong.” I, for one, look forward to learning more about it, and seeing where it can challenge what I think I know.