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Do the Diamondbacks understand DIPS theory?

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The Diamondbacks have paid a high price for two pitchers who appear to be overvalued by traditional measures like ERA.

Jim Brown-USA TODAY Sports

The Diamondbacks have made a lot of noise so far this offseason by acquiring two starting pitchers in Zack Greinke and Shelby Miller. Like the Padres of a year ago, the Diamondbacks appear to be "winning the offseason," and some have already going so far as to call the Diamondbacks a "dangerous" team for 2016. I'm not ready to jump on the bandwagon just yet, as the Diamondbacks are still a flawed team coming off a 79-win campaign. Two moves do not necessarily turn a non-contender into a favorite to make the playoffs.

What strikes me most about these deals, though, is the fact that the Diamondbacks appear to have massively overpaid in both instances, particularly given each pitcher's fielding independent numbers. In this day and age, it seems to be a given that teams understand the value of DIPS theory, which was first articulated by Voros McCracken all the way back in 1999. DIPS stands for defense independent pitching statistics, and these measures (FIP, xFIP, etc.) attempt to evaluate pitchers based on statistics they have almost total control over, including strikeouts, walks and home runs. There can be a lot of variation between a pitcher's ERA from one year to the next because of factors outside a pitcher's control. Fielding independent numbers can give us a better sense of a pitcher's true talent level, and they can also be helpful for predicting a pitcher's performance going forward.

In their two big moves this offseason, the Diamondbacks have invested a lot in pitchers who are not loved by fielding independent metrics, at least relative to traditional measures like ERA. I wrote about Shelby Miller a couple weeks back, noting that Miller's substantial career ERA-FIP gap (3.22 vs. 3.82) was unlikely to continue since he does not have the skills needed to maintain a high strand rate and low BABIP. Miller's projections certainly seem to indicate that he is due for some regression going forward: Steamer projects Miller to post a 4.09 ERA and 4.22 FIP in 187 innings next season, good for 1.7 fWAR. At best, that is the stat line of a mid-rotation starter, and while Miller has some upside, he is only under team control for three seasons.

ZiPS likes Miller a little more, projecting him for a 3.65 ERA and 3.0 WAR in 185 innings. However, ZiPS also likes Ender Inciarte almost as much, projecting him for 2.8 WAR in regular playing time in 2016. If we assume that Inciarte provides slightly less value than Shelby Miller, then this trade might make sense as a as a one-for-one swap, since Inciarte is under team control longer than Miller (five years vs. three). What makes this deal so lopsided is the fact that the Diamondbacks also gave up Dansby Swanson and Aaron Blair, two of their top prospects. The Diamondbacks have shown a tendency to undervalue their prospects, but they still had to dramatically overvalue Miller if they were willing to give up such a package to acquire him.

The Diamondbacks also paid a heavy price to sign free agent starting pitcher Zack Greinke. His six-year, $206.5 million contract set a record for the highest average annual value ($34.4 million) ever given to a major league player, topping the David Price deal by more than three million per season. Greinke got this contract in large part due to his 1.66 ERA in 2015, the lowest in a single season since Greg Maddux in 1995. The only problem with paying Greinke for this kind of production is that he is unlikely to come anywhere close to repeating it in the future. His .229 BABIP and 86.5 percent strand rate were extreme outliers, both compared to other major league players and Greinke's own career norms.  His FIP this past season was a much more reasonable 2.72, and he was 7th in baseball with 5.9 fWAR.

Going by Steamer and ZiPS projections, Greinke is likely to see significant regression moving forward. ZiPS projects Greinke for a 3.08 ERA and 4.2 fWAR in 2016, and these numbers will likely decline further as Greinke ages. And although full ZiPS projections are not available for all players yet, we have this tidbit from ZiPS creater Dan Szymborski.

Using Greinke's ZiPS projection and a dollar per WAR value of $6.5 million, Szymborski calculated that Greinke's value over the life of his contract will be a good deal less than what he is being paid.

The Diamondbacks may also have to worry about the fact that Greinke is already 32 and has dealt with a nagging elbow issue. He reportedly received a "lubricating injection" in his elbow back in February, and this was the third Spring Training in a row that he had underwent such treatment. This could be nothing to worry about, but we know that pitchers are always at risk of missing a significant amount of time due to an arm injury. Clearly, this type of risk needs to be factored in when signing a pitcher to a long-term contract.

Maybe the Diamondbacks have reason to believe that Miller and Greinke will continue outperforming their FIP as they did in 2015. It is true that each pitcher generated soft contact at a rate well above league average in 2015, according to FanGraphs. Still, outperforming one's FIP is a finicky thing, and many pitchers appear who appear to have this skill do not end up sustaining it over an extended period of time. Miller does not seem to possess the ability needed to outperform his FIP going forward, and Greinke's career FIP is actually lower than his ERA, despite his excellent 2015 season.

Ultimately, I believe that there are plenty of people in the Diamondbacks' front office that understand the importance of evaluating pitchers using better metrics than ERA. Despite their reputation, the Diamondbacks appear to be developing a strong analytics department, and they are making a conscious effort to utilize all of the data at their disposal. With that being said, there is a big difference between having an analytics department and actually using analytical information in valuable decision-making processes. The best analytical organizations have buy-in from employees top to bottom, from the low-level interns all the way up to the GM and perhaps even the owner. Based on what we have seen and heard from people like Tony LaRussa and Dave Stewart, the Diamondbacks do not yet have this level of buy-in from some of their most important decision-makers, which could hurt their organization for years to come.

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Nick Lampe is a featured writer at Beyond the Box Score and Viva el Birdos. You can follow him on Twitter at @NickLampe1.