Much has been made recently over the growing concern about baseball's addiction to the strikeout. With the New York Times, the Wall Street Journal, and Sports Illustrated writing about the issue just the last week, it would seem that the alarm has finally gone mainstream.
Those articles primarily attribute strikeout inflation to bigger, better, and stronger pitchers with better stuff than those in the past. All that may be true to some degree, but their contributions to the strikeout pandemic are most definitely overstated.
Last week I wrote about the steady rise in Called Strikes over the last few decades and what that says about the rise in K-rates. By gathering that the called strike has increased while the swing-and-miss strike has remained stable, it would seem that a changed philosophy of hitters is likely to have caused most of this increase. Batters of the modern era are simply more willing to allow themselves to strikeout than ever before.
Over time, hitters, managers, and front offices have slowly recognized more and more that they can trade additional strikeouts for an increase in production at the plate with very little repercussions. The result of all this is a sort of asymmetry that can be confusing for fans:
Strikeouts = good for pitchers. Strikeouts = not bad for batters.
Based on a few confused comments over at reddit, I would like to address this concern over the asymmetry.
Good for pitchers
This is the easy part to understand, obviously. The more a pitcher strikes out the batters he faces, the less dependent he is upon both his defense and pure dumb luck on balls hit to his fielders. The strikeout is a sure out, the ball in play could be anything.
(Sure, maybe you can induce weak contact and gain nearly-sure outs on fewer pitches, maybe you are Greg Maddux, maybe we'll see the likes of you again this century. But, also, maybe not.)
For this reason, we tend to compare pitchers' strikeouts against balls in play, rather than ball in play outs. Because many years ago, Voros McCracken discovered that pitchers have far less control over what happens to the ball after it leaves the bat than we had previously thought.
Today, we see that year-to-year BABIP for hitters correlates much stronger for batters (r = .35) than it does for pitchers (r = .20).
Not so bad for hitters
This is the part that's confusing. How can a strikeout be the best thing for the pitcher and not the worst thing for the batter?
Unlike pitchers, batters have a bit more control over the outcome of a ball in play. So it is more than simply a matter of putting the ball in play versus not putting the ball in play. For batters, an out is an out.
By linear weights, the strikeout is worse than a ground out or fly out, but just barely:
Run Values for Outs
|-0.27||Dropped Third Strike|
|-0.30||Foul Fly Out|
|-0.40||Caught Stealing Double Play|
|-0.72||Non Force GIDP|
Advancing the runners while retiring to the bench and making "productive outs" is preferable to simply retiring to the bench, sure. A ground out is typically worth .06 of a run more than a strikeout. But for some reason, this talking point has become noticeably overstated in baseball circles.
This .06 of a run is therefore a small price to pay when we think of how it boosts the batters production at the plate. If we look at the weighted averages of all hitters from 2002-2012 with at least 500 PA, we find that hitters with the highest strikeout rates have wOBAs just as high as hitters with lower strikeout rates. Moreover, they have a significantly higher wOBA than hitters with lower strikeout rates:
Strikeouts and wOBA 2002-2012
|K%||wOBA||# of batter-seasons|
As a hitter, allowing yourself to strikeout more does not necessarily lead to more power, but it certainly doesn't hurt your chances. It presumably allows you to swing harder, swing quicker, and swing earlier. In which case, you are bound to whiff often, and your strikeout rate will spike. But occasionally you hit the ball on the screws and the pay off then becomes a ball in the seats, or a gapper off the wall in right-center for extra bases.
NOTE: It is important to remember that his table does not address the issue of survivor bias. Players who have high strike out rates with no power to off set their inability to make contact will not 'survive' in the majors as often to reach 500 PA.
Relationship between K% and success
The correlation between K% and wOBA for that same sample of batters is small at r = .12, suggesting that if anything wOBA increases by the slightest margin as K% increases. Not so bad for those hitters.
Pitcher's K% has a much stronger correlation to ERA at -.52, however, using a sample of 1071 pitchers from 2002-2012 with at least 150 IP for the season. Clearly, very good for pitchers.
This is an important aspect of the modern game that deserves to be explained clearly. I personally know of some very informed, very passionate fans of the game that still have trouble reconciling that batters and pitchers value strikeouts differently, if not oppositely. It may take some time to realize that the two parties are actually playing two different games when they face off against each other at the plate.
If you feel like you can help contribute to clarify this lopsided valuing of the strikeout for some of our readers by either metaphor or math, I encourage you to leave us a few comments in the section below.
. . .
James Gentile writes about baseball at Beyond the Box Score and The Hardball Times. You can follow him on twitter @JDGentile.