Scorecasting (19 page)

How do we know this? One of the problems with testing the
effect of crowd support is that almost every feat is a function of not only the player and the crowd but also the defender, other teammates, the defender’s teammates, and the referee. How do we isolate the crowd effect from all these other potential influences on the player? We need to look at an area of the game divorced from all these factors, such as
free throws. Free throws are an isolated interaction between one player—the shooter—and the crowd that is trying to distract and heckle him. Also, all free throw shots are standardized; they are taken from the same distance of 15 feet at a basket standing 10 feet high regardless of where the game is played.

Over the last two decades in the NBA, including more than 23,000 games, the free throw percentage of visiting teams is 75.9 percent and that of home teams is … 75.9 percent—identical even to the right of the decimal point. Are these shooting percentages any different at different points in the game, say, during the fourth quarter or in overtime, when the score is tied? No. Even in close games, when home fans are trying their hardest to distract the opponents and exhort the home team, the percentages are identical. Sure enough, as sluggishly as the Blazers played in San Antonio, they would make 15 of their 17 free throw attempts (88.2 percent) even with fans behind the basket shouting and waving. The Spurs, by contrast, would make 75 percent of their attempts. Evidence of the crowd significantly affecting the performance of NBA players is hard to find.

What about other sports? In hockey, there’s a rough equivalent to free throws we can use to gauge the crowd’s potential influence on players. Beginning in the 2005–2006 season, the NHL adopted the “shootout” to settle ties in regular season games if the game remained tied after the standard overtime period. In a shootout, each team chooses three players to shoot one on one at the goalie. (Tournament soccer has a similar procedure with penalty kicks at the end of a tied game.) The team with the highest number of goals scored wins.

In the 624 games decided by
shootouts in the NHL from 2005 to 2009, home teams won 308 (49.4 percent) and away teams won
316 (50.6 percent). In other words, for shootouts—held during clearly important times in the game when you’d expect the crowd to be
especially
involved and boisterous—the significant home ice advantage normally present in the NHL
evaporates
. When playing at home, shooters are no more successful than they are on the road. And when they’re not successful, it is not because goalies are better at blocking shots at home as opposed to on the road, either. In a shootout, shooters are successful 33.3 percent of the time at home and 33.5 percent on the road, and goalies stop 51.5 percent of shots at home and 51.6 percent on the road. (About 15 percent of the time both home and away shooters miss the goal entirely.) If hockey fans aren’t adversely affecting opposing players—or having a beneficial impact on the home team—during the most tense moments in a tie game, isn’t it safe to assume that their support isn’t affecting much when it’s, say, midway through the second period? (There is a similar disappearance of home field advantage in tournament soccer penalty kicks.)
^*

In football, we could look at punters or kickers, who aren’t exactly in total isolation from the rest of the players on the field, but pretty close. It turns out that yards per punt are identical for home and visiting punters (about 41.5 yards). Likewise, field goal success from the same distance and extra point accuracy are identical for kickers at home and on the road (about 72 percent on average).

Of course, punters and kickers are just two players, and you could question whether either has the ball long enough to be affected by a rabid crowd. Fair enough. Unfortunately, there isn’t another isolated activity within the game of football we could point to in order to measure crowd influence outside everything else going on in the game. Instead, we could look at a number of offensive and defensive statistics to see where home teams fare better than visitors, recognizing that these advantages could
come from a host of sources, including the crowd. It turns out that NFL teams rush better at home. They rush more—no surprise there since home teams are ahead more often—but also gain more yards per rushing attempt. Visitors, by contrast, pass more than the home team because they are usually behind and need to make up points in a hurry. But interestingly enough, visiting teams pass slightly
better
than home teams. (Who knew? NFL quarterbacks are a little better on the road than at home.) Though we might speculate that extreme crowd noise distracts visiting quarterbacks and makes their commands inaudible to their teammates, it doesn’t seem to affect their performance. Thus, at least with respect to this aspect of the game, it’s hard to say crowd noise contributes to the home team’s success.

In baseball, the closest we can come to measuring the crowd’s influence is to examine the pitcher. Not his ball-strike count—influenced, as it is, by the batter, the umpire, and the game situation—but his velocity, movement, and placement. We got the data thanks to the
MLB.com
technology Pitch f/x. A computer generates the location of the pitch, the height of the ball when released from the pitcher’s hand, the speed at which the ball travels when it leaves the pitcher’s hand as well as when it crosses the plate, and the degree to which the ball’s direction changed or diverged from its path to the plate, both horizontally and vertically. Baseball researchers and Sabermetricians have been busily gathering and applying the data to answer all sorts of intriguing questions: Who has the nastiest sinker? How is Red Sox ace
Josh Beckett’s fastball different from his breaking ball? (For the record, his changeup has as much movement as his fastball, a big factor in his success.)

We obtained the last three years of these data, covering more than 2 million pitches, to answer a different question: Do pitchers actually pitch differently at home versus away? Before the Pitch f/x data existed, you couldn’t really answer this question. You could only ask if the outcomes—balls or strikes—from pitchers were any different at home versus away. But again, outcomes are dependent on pitch selection, hitter reaction, umpire response,
and game situation. Now, with the Pitch f/x data, we can simply ask: When Josh Beckett throws a fastball at Fenway, does it have more velocity, more movement, and better placement than it does when he is on the road?

Much like NBA players shooting free throws, on average Major League pitchers are equally accurate at home as on the road, throwing a ball within the strike zone 44.3 percent of the time at home and 44.5 percent of the time on the road. Pitches more than 1.5 inches outside the strike zone occur just as frequently at home as on the road (46.5 percent of the time). Even the most extreme pitches, those way out of the strike zone or those that hit the dirt, occur no more frequently on the road than at home.
^*
In addition to having identical accuracy at home and on the road, pitchers throw with the same velocity—87 mph on average when the ball crosses the plate—and movement no matter where they play. We repeated these numbers for the same kind of pitch, categorized by Pitch f/x into changeup, fastball, curveball, four-seam fastball, split-fingered fastball, cut fastball, sinker, slider, and knuckleball, and found no difference in speed, movement, or placement for the same type of pitch by the same pitcher at home versus on the road. We tested the first inning versus later innings. Again, there was no difference. We tested different pitch counts. No difference. We even tested different game situations. Again, no difference. Pitchers appear to pitch no differently along any dimensions we can measure at home versus on the road, suggesting that neither the crowd nor the optics of the stadium influences their performance.

We can also use the Pitch f/x data to help gauge whether playing at home has any impact on batters. Controlling for all the factors that might make a batter hit better at home is nearly impossible, but we can control for a lot by looking at identical pitches—same speed, location, movement—in identical situations, home versus away. Does
David Wright, the New York Mets’ star
third baseman, hit a waist-high, middle-of-the-plate, 90-mph fastball on a two-two count better at home, where the crowd is supporting him, than on the road, where he might be getting booed?

Location may be the key to real estate, but when it comes to hitting a baseball, for the average Major Leaguer geography doesn’t matter. When a player swings at a pitch in the strike zone, his probability of hitting the ball is exactly the same at home and away. For pitches outside the strike zone, batters also fare equally at home and on the road. They are no more likely to swing at the same pitch at home than on the road and demonstrate no greater ability to swing at better pitches at home.

Of course, it could be the case that the crowd influences other aspects of the game—pumping up home teams to play better defense, encouraging them to greater effort. We can’t rule this out, nor can we measure or isolate the crowd effect on these aspects of the game from other things going on at the same time. What we
can
observe is that in situations in which many of these other influences are “turned off” or controlled for, the crowd seems to have no effect. If the crowd is ineffectual in these isolated situations, it is at least questionable how much of an effect it could have in other situations.

Hey-batter-batter-batter-swing?
Sorry, but he’s going to do it equally well whether you’re chattering or not. Just as he’s going to shoot free throws, kick field goals, and deke the goalie comparably well whether you’re encouraging him or cursing him.

By the end of the first quarter, the Spurs led comfortably, 29–20. The Blazers were shooting poorly, were committing scads of mental errors, and were conspicuously sluggish on defense. They were late to rotate, made only halfhearted efforts to block shots, and generally treated the lane as if it were a zebra-striped crosswalk:
No, really, after you. Go right ahead!
Portland’s coach,
Nate McMillan, would later observe that his players were “a step slow.”

Who could blame them? The Blazers had played in Houston the previous night, boarded a plane, landed in San Antonio after midnight, and then taken a bus from a private airstrip to the hotel. Some players reported that they didn’t fall asleep until dawn. As anyone who’s taken a red-eye flight can attest, the grind of travel—the sitting, the dislocation, the time changes—can exact a steep price on the body. All the more so when the itinerary mirrors that of an NBA team pinballing randomly to Indianapolis one night, to Phoenix the next, and over to Dallas a few nights later. Your circadian rhythms are thrown off; your immune system can betray you. At the hotel, everything from the lumpy pillows to the inevitably ill-timed knock from the minibar stocker to the inadvertent wake-up call militates against a good night’s sleep. It makes sense that the athletes who slept on their favorite pillows and woke up in their own beds that morning will outperform the ones who flew in earlier that morning. Particularly so for a team such as Portland, which—thanks to the Seattle Sonics relocating to Oklahoma City—is a significant flight away from every other team in the league.

We submit, however, that the travel doesn’t much matter. The rigors of the road exist, but they don’t underpin the home court advantage. Why do we say this? Consider what happens when teams from the same (or a nearby) city play each other, when the Los Angeles Lakers play the Los Angeles Clippers in the NBA—the two teams share the same arena—or the New York Rangers play against the New York Islanders or the New Jersey Devils in the NHL. For these games, the “rigors of travel” are nonexistent. Everyone is in his natural time zone and sleeping in his own bed. Yet if you look at all these “same city” games, you find that home teams have the exact same advantage they do in all the other games they host. Likewise, road teams don’t lose more often when they travel greater distances. Controlling for the quality of the opponent, the San Antonio Spurs, for example, fare no better when they take puddle-jumpers to play the Dallas Mavericks and Houston Rockets than when they make longer trips to Boston, Toronto, and Miami.

We can take this one step further in the NHL, looking at games that involve not only long travel distances but also border crossing—which can require negotiating customs and other procedures that generally increase the pain of transit—by examining U.S. teams that play in Canada and vice versa. Yet we find no abnormal home ice advantage for U.S. teams visiting Canadian teams or vice versa, even for those farthest from home.

In Major League Baseball the rigors of travel aren’t a significant issue, either. Just as in the NBA and NHL, for games involving teams from the same metro area—interleague play between the Chicago Cubs and White Sox, New York Yankees and Mets, Los Angeles Dodgers and Angels, San Francisco Giants and Oakland A’s—the home teams win at
exactly
the same rate at which they normally do. We also know that home field advantage has been remarkably constant over the last century; it was virtually the same in MLB from 1903 to 1909 as it was from 2003 to 2009. This suggests that the teams jetting on chartered flights with catered meals, high-thread-count linens, and flat-screen televisions have no more success than did the teams that traveled to games in Pullmans and buses. (Either travel isn’t causing the home advantage or teams need to rethink their jet purchases and the on-flight catering.)

Nor do the rigors of travel play much of a role in the NFL’s home field advantage. Teams play only one game per week and in fact usually depart for a game a few days in advance to acclimate. As with the other sports, when nearby teams play—Oakland Raiders versus San Francisco 49ers, New York Giants versus New York Jets, Baltimore Ravens versus Washington Redskins—the home field advantage holds firm at its normal level.