Shift Morneau Shift?
Inspired by my possible doppelganger Ben Lindbergh, I decided to revisit the topic that brought me to this here very site: the shift. Ben wrote an in-depth piece at Baseball Prospectus about J.D. Drew and the shift on Monday, concluding that, "We don’t know precisely how Drew would respond to an escalation of the shift, and if the current state of affairs persists, we never will, but it’s probably worth it for teams to find out; it seems fairly certain that Drew is winning this battle of offense-against-defense game theory thus far." So my question is, who else might benefit from an altered defensive alignment?
Max Marchi and Ricky Zanker have explored aspects of graphing batted ball distributions. Building on their work, I came up with my own model. Using MLBAM-provided batted ball location data from 2008-present and Peter Jensen's gameday translations, I found the batted ball angle of all non-bunt grounders from left-handed hitters with no one on base, as well as whether or not the batter reached safely. I sorted the data into two groups, the first of which contained 2,500 grounders from 15 "shifted" batters, your Howards and Giambis. The rest of the 32,000 grounders formed the second group. I then fitted a binomial LOESS smoothing curve to the data. Here is the resulting model:
Allow me to explain. The top portion of the graph shows BABIP on grounders. There are three big differences between the red line (shift) are the blue line (no shift). First, at -15 degrees, shifted players have the benefit of a vacated shortstop position, and are therefore better than twice as likely to pick up a hit on a batted ball to that vector. Next, at 0 degrees, straight up the middle, shifted players have under a 50% chance at reaching base, while non-shifted players are up above 60%. And finally, balls directed toward the 3-4 hole are much more likely to go for hits when there is no shift. So, to sum up the obvious, implementing a shift allows hits on batted balls toward left field, but in exchange, balls up the middle and in the hole are converted into outs at a higher rate. On the bottom of the graph is a histogram. On average, shifted players hit a higher percentage of balls toward the second baseman, and many fewer balls toward the shortstop. The other notable difference is that shifted players have hit fewer balls up the middle than their counterparts, even though the defense is aligned to prevent hits on balls up the middle.
While it would be nice to have reliable measures pf batted ball speed and batter speed (the two other considerations that help determine groundball average), I had to make do without. So I predicted both of the above fits against my dataset to come up with expected averages for shift and no shift. Here's how the shifted players stack up:
"Angle" is the average batted ball angle. "BABIP" is the rate at which the batter reaches base safely. "No Shift" is the predicted BABIP using the no shift model, and "Shift" is the predicted BABIP using the shift model.
You might notice that the league-average BABIP on non-shifted players is 20 points higher than it is for shifted players. This doesn't mean that the shift uniformly lowers BABIP by 20 points. This means that the type of player who gets shifted is bad at reaching base via groundballs. So when comparing the two models, keep the averages in mind, and for players who are speedy, such as Jimmy Rollins, understand that the shift may not be a viable option.
I might be wrong about Justin Morneau, and maybe he isn't shifted regularly, but if he is, it's a mistake. So when it comes to Shift Morneau Shift,* I say "No Shift!"
*Credit to my friend Pat for starting the baseball T.V. shows Twitter topic and my buddy Steve for coming up with Deal Morneau Deal.
Carlos Pena has far and away the most skewed groundball angle toward his pull side. Most of these guys are obvious shift candidates. Fielder and Morneau maybe not so much. But these aren't the only players for whom the shift matters. So how about the non-shifted guys?
I found the difference between the "Shift" column and the "No Shift" column for those batters with at least 25 groundballs hit. Three rookies and J.D. Drew himself top the list. Brennan Boesch, Jason Heyward, and Ike Davis have all been hugely successful, exceeding even the most optimistic of expectations. But maybe their pace will slow once defenses learn how to play them. The exaggerated infield shift is certainly an option. It's also likely that their luck will soon run out, as their grounders have simply found holes. Luck has nothing to do with J.D. Drew's success on grounders. If people would just take a look at his spray chart data, they'd know to shift him, but unfortunately, too many are of the line of thought that it doesn't matter how you play him, since he's hit 30 homers in a season only once and is paid $70 million. J.D. Drew does something funny to people's minds.
Here are five players I would strongly consider shifting against, followed by the rest of my dataset.