Last week, in the wake of Armando Galarraga’s near-perfecto, I took a stab at explaining the recent spate of no-hitters and perfect games. Today’s Prospectus Hit and Run examines the myriad claims that we’re in the midst of a so-called “Year of the Pitcher.”
As usual, my first impulse is to debunk such claims. Scoring is down to 4.47 runs per game through Sunday, 3.1 percent below last year’s rate, to its lowest level since 1992. I offered three potential explanations for the phenomenon:
- Weather: It’s only mid-June and we’ve yet to experience the warmest months, when scoring should theoretically increase as the ball carries better.
- Interleague play: The American League has dominated interleague contests in recent years, scoring at a higher rate than in intraleague play. Since we’re only one-third of the way through the interleague schedule, scoring levels are a bit lower than expected.
- New ballpark: This year, the Junior Circuit added the Twins‘ Target Field to its rolls. Spacious and exposed to the elements, the pitcher-friendly park replaces the climate-controlled Metrodome, where scoring rates were higher.
Alas, the lowered rates more or less persist in spite of these explanations. Based upon recent history, there’s not a big “Wait Till It Warms” effect; rest-of-season scoring (from mid-June onward) is up 0.01 runs per game from early-season rates over the past 10 years, and 0.07 runs per game over the last five. The AL — where scoring is down 5.4percent, compared to 0.7 percent in the NL — has a recent advantage in interleague play which might show itself more in the remaining two-thirds of the interleague slate, but while their five-year rate is higher than in intraleague contests, last year it was actually lower.
As for the ballpark question, controlling for the Metrodome/Target Field swap lowers the annual change from 3.1 percent to 2.6 percent. It’s worth noting that six of the seven newest parks are hosting below-average scoring rates, and that BP’s multi-year park factors (which include some regression to the mean for newer parks) credit the newest parks (Target, Yankee, Citi, Nationals, Busch, Citizens, Petco) with reducing scoring by 2.5 percent. So from a longer-term standpoint, there’s definitely something to the ballpark theory.
The most compelling evidence in favor of the “Year of the Pitcher” designation is that strikeout rates are at an all-time high, occurring in 18.1 percent of all plate appearances this year. K rates have shot up a full percent over the past three years, perhaps due to philosophical shifts on both sides of the ball, with teams viewing strikeout pitchers as ever more important, but worrying less about hitter strikeouts because they correlate well with positive offensive events. Perhaps the latest waves of technology — specifically high-definition TV and the Pitch f/x data system — are making umpires more conscious about calling strikes, because our power for second-guessing is at an all-time high (just ask Jim Joyce).
Even so, such claims about the YoP are probably overstated. BABIP rates, whose rise has mirrored those of scoring rates, are down only a point from last year, and well within the range we’ve seen over the past decade, and Power Factor (paleo-sabermetrician Eric Walker’s measure of total bases per hit, a metric I’ve cited before in such matters, and one which correlates extremely well with the modern rise of scoring rates) is down only by an eyelash, suggesting that the underlying conditions via which the game is played haven’t fundamentally changed.
So color me skeptical as to whether there’s anything to these “Year of the Pitcher” claims beyond a more or less random clustering of some spectacularly entertaining pitching feats (Ubaldo Jimenez’s no-hitter, Dallas Braden and Roy Halladay’s perfect games, Galarraga’s near-miss, Stephen Strasburg’s debut et al). Scoring will likely wind up below last year’s rate and may indeed come in at the lowest rates since 1992, but we’re hardly headed towards revisiting the days of Bob Gibson.