On the other hand, it is pretty well accepted that Adam Jones has bad plate discipline. Bucs Dugout asserts that Adam Jones swings at pretty much everything. Peter Gammons claims that his major problem is that he swings too often in favorable counts. Camden Chat says that it’s indisputable that he strikes out too much and walks too little.
In this article, I intend to show that Chris Davis has significantly worse plate discipline than Adam Jones, despite the fact that Davis has a BB/K of roughly .4 while Jones has a BB/K of roughly .2 over the past three years. Here, let me explain.
Recently, I wrote a post breaking wOBA into three component parts using data from ESPN Stats and Information. I measured a player’s production when he hits a pitch in the strike zone, when he hits a pitch that isn’t in the strike zone, and when he doesn’t make contact at all. Using this method measures each player’s production in these three areas as shown in the chart below.
Chris Davis averages a wOBA of .187 on balls not put into play compared to Adam Jones who averages a .136 on balls not put into play from 2013-2015. This makes sense as Chris Davis does walk more often than Adam Jones and would seem to support the argument that Davis has better plate discipline. However, such an analysis ignores one crucial thing. It ignores the fact that Adam Jones failed to put the ball into play 24% of the time while Chris Davis failed to do so 44% of the time.
This is relevant due to a point that I made in my previous post. For the average batter, a strikeout is more damaging than a walk is beneficial. Batters only have a .219 wOBA on average when failing to put the ball into play and nearly all do better when they put the ball into play than when they fail to do so. The general rule of thumb is that it takes roughly 11 walks to offset 9 strikeouts because batters average a .369 wOBA when putting the ball into play.
In order to compare Adam Jones’ plate discipline to Chris Davis, it is necessary to take into account the fact that Chris Davis doesn’t put the ball into play as often. Just comparing .187 to .136 fails to take quantity into account.
The way to take into account both quality and quantity requires some high school algebra. It requires comparing how Adam Jones actually performed to how he’d perform if he put a pitch into play only in 56% of PAs and failed to do so in the other 44% but had the same wOBA when not putting the same ball into play as Chris Davis. In other words, this is equivalent of determining which equation is greater:
.76 * wOBA Jones InPlay + .24 *wOBA Jones NotInPlay orIn other words, it’s necessary to compare how Chris Davis performs during the 44% of times when he fails to put the ball into contact to how Adam Jones performs during the 24% of times he fails to put the ball into contact AND another 20% of how he performs when he does put the ball into contact. This results in the following.
.56 * wOBA Jones InPlay + .44 *wOBA CD NotInPlay.
Which simplifies to:
.2 * wOBA AJ InPlay + .24 wOBA AJ NotInPlay vs .44 * CD wOBA NotInPlay
When one takes both quantity and quality into account, it becomes apparent that a player able to hit the ball as successfully as Adam Jones would rather have his walk and strikeout numbers rather than having Chris Davis’s. Even though Chris Davis has a better BB/K and a wOBA Not in Play than Adam Jones, the fact that he puts so many fewer balls into play hurts him.
I make two assumptions for this analysis. I assume that Adam Jones will hit the same proportion of pitches in the strike zone or not in the strike zone if he makes contact less frequently and that his production when he does make contact won’t increase if he swings less frequently. Preliminary research suggests that these assumptions are slightly inaccurate. He should be expected to make slightly better contact if he swings less frequently.
The wOBA All Balls Field projects how Adam Jones would perform if the extra in play contact was solely against pitches out of the strike zone and thus balances out both of the assumptions in the paragraph below. Even still, one would rather have Adam Jones’ numbers than Chris Davis’s strikeout and walk numbers. In reality, as shown in the chart above, Chris Davis’s plate discipline is about as good as Jonathan Schoop’s and only slightly better than Jimmy Paredes.
This poor plate discipline shows why it’s so hard for Chris Davis to be successful. My metric measuring plate discipline suggests that he’s typically in the bottom 2% in this regard (5th percentile in 2014). He’s able to thrive because in 2013 and 2015, he was in the 99th percentile of wOBA for pitches hit into play. He was elite in those years because he was able to kill the ball whenever he hit it. In 2014, he was in the 86th percentile in wOBA for pitches hit into play. As soon he drops from elite to very good in wOBA for pitches put into play, he becomes an average hitter.
As the chart below shows, when he’s in the 99th percentile for wOBA for pitches in play, he’s in the top five percent of all batters. If he drops to just the 95th percentile for wOBA for pitches in play, all of a sudden he’s down to the 77th percentile of all batters. If he drops to the 90th percentile, then he’s in the 65th percentile of all batters. Once he drops to the 75th percentile for wOBA for pitches in play, he’s in the 36th percentile of all batters and is a DFA candidate. The takeaway is that he can still be one of the best batters when putting pitches into play and still be worthless. The chart below shows where he ranks based on his wOBA for pitches in play.
The news gets even worse. On Twitter, Jon stated that he felt that Chris Davis had a good chance of becoming ineffective due to a collapse in offense if his contact rate drops any further because his walking ability is an indirect effect of his hard contact. I figured that was unlikely because I presumed that Davis will be average offensively before his ability to make hard contact degrades significantly. But when I looked at the data, it became clear that one could argue that Davis always had elite numbers when putting pitches into play but struggled earlier in his career because he hits few pitches in the strike zone compared to other batters and had a poor walk vs. strikeout ratio.
In addition, while Adam Dunn, Carlos Pena, and Jarrod Saltalamacchia each became ineffective once their wOBA when putting pitches into play degraded, it would appear that Melvin Upton and Ryan Howard started to become ineffective when their plate discipline degraded. It seems reasonable to presume that Chris Davis will start struggling if his primary competency of hammering pitches put into play starts to falter or if his plate discipline becomes significantly worse. It’s reasonable to argue that Jon and I both have reasonable chances of being right.
Chris Davis probably won’t become ineffective immediately, but should before his contract ends. There are a few encouraging outliers though. David Ortiz didn’t stop being elite in this regard until he was 36 while Nelson Cruz is still elite at 35. Davis’s contract only runs through 36 so if he can take after those players then the Orioles will likely be happy with the results of this signing. On the other hand, Ryan Howard started struggling at 32 and Adam Dunn started struggling at 31. This contract may look ugly if the Orioles only receive three years of strong performance from Davis.
This article shows that most players would rather have Adam Jones’ walk and strikeout percentages rather than Chris Davis. If so, this suggests that plate discipline is largely misunderstood and that a metric similar to K-BB should be used for both hitters and pitchers. With a few exceptions for players like Nori Aoki and Alberto Callaspo, it is better to put the ball into play than not. Indeed, in 2013, Chris Davis had a .657 wOBA when putting a pitch in the strike zone into play while a player that walked in every plate appearance would have a .690 wOBA. It's easiest for batters to be successful by putting the ball into play.