Baseball: The home team advantage in extra innings

The Game Room
1

I had a nice week with my 11 year old daughter. She has really taken to baseball in the past year and, as her father, I have explained all of the unwritten rules and folklore that surrounds the game.

This past week, the Pirates and Dodgers headed into extra innings at PNC Park. At some point, I mentioned the commonly held belief that the Pirates, as the home team, had the advantage in extra innings.

Of course, she asked why.

Always ready with a baseball response, I told her what I had been taught:

For example, going into the bottom of the 10th inning, all the Pirates have to do to win the game is to score a run. If they do that, they don’t have to face the Dodgers again in this game. One run, any way you can get it=a Pirate win.

What do the Dodgers have to do? They must hold the Pirates scoreless in the bottom of the 10th. They must then bat in the top of the 11th and score at least one run. IF they score that run, they must then hold the Pirates scoreless again in the bottom of the 11th.

The Dodgers must get at least 6 outs AND score at least one run to win. The Pirates must only score one run to win without the need to retire a single Dodgers hitter.

I was sufficiently satisfied with my answer; the same one given by my father to me and his father before him, and likewise his father to him; rinse and repeat back to the Norman conquest of England in 1066.

But then my 11 year old was having none of it and accusing me of misrepresenting the scenario. She pointed out that I was taking away from the Pirates accomplishment. She stated that going into the bottom of the 10th, the Pirates had already faced the Dodgers 10 times while the Dodgers had only faced the Pirates 9 times. Any advantage was earned by the Pirates and not as a result of being the home team.

Yes, I wisely pointed out, but by virtue of being the home team, they were now in this favorable position. She countered that it wasn’t by being the home team, it was by getting the Dodgers out 10 times instead of 9. The Bucs earned it.

Yes, darling, but they could only earn it because they are the home team. Visitors can never be in the position of scoring one run and walking off. She countered that they cannot be in that position because they never earned that position: Why should I assume that the Dodgers would have gotten to that position had they been presented the opportunity?

As it was late, I’ll admit I didn’t have an answer for that. Each team gets three outs per inning no matter if it is taken first or last. There is no advantage or unfairness.

So where is this advantage? Damn kids. :slight_smile:

2

Sounds like your explanation is too complicated. The home team has an advantage because they win as soon as they score. If the visitors score, the home team has a shot at getting runs back.

An obvious example was Game 6 of the 1986 World Series. The Red Sox scored two runs in the 10th. If they had been the home team, the game would have been over at the first run. But the Mets were at home and scored three runs to win it.

There also a general home team advantage for every game. From 2010-2014, home teams have a .537 winning percentage; visiting teams have a .463 winning percentage.

3

I don’t understand what you’re asking about. The home team batting last doesn’t give them any real advantage. In baseball each team faces each other for an equal number of half innings. By batting last the home team may end the last half inning early because they win once they go up one run, and that’s because there will be no more innings.

The home team advantage has to do with familiarity of the park, having the fans rooting for you, and not having to travel to play the game, not who bats last.

4

Any advantage the home team gets by batting last is entirely psychological. That can be a significant factor, but it’s no physical advantage. Whether the psychological situation you’re faced with makes you perform worse or better is inherently personal, but it makes some sense that in general people might try just a bit harder if they know their efforts will cause their team to win immediately.

On the other hand, losing on the road (in 8 innings defensively) means you get to rest your pitchers a bit more.

5

The kid is basically right. That the home team’s last turn at bat confers an advantage is yet another baseball myth–possibly with some psychological effect but not the concrete structural one that everyone believes. (BTW, the book Scorecasting argues that the most measurable basis for home advantage in late/close situations is actually umpire bias, such as in called strikes.)

6

With all else hypothetically equal, if the Red Sox had been the home team, the Mets would have already had their turn at bat in the 10th and would have been up 6-3.

7

There is an advantage that I’m surprised no one has mentioned. In the bottom half of any extra inning, the home team knows exactly how many runs it needs to win. In the top half, if the first batter for the visitors singles, do you sacrifice him to second. Baseball wisdom tell us it increases your changes for getting a run, but it certainly decreases your chances for two runs so you might or might not do it.

As the home team you would know if one run is enough to win so sacrifice. If you’re two runs down, definitely don’t sacrifice.

Similarly if you have a runner on second and one out and the batter singles, do you try to score the runner from second? The visitors have more of a guess. One run is very important. But you decrease your chances for two runs. As the home team, you probably send him if you’re tied or one run down. If you’re two runs down you definitely hold him at third.

8

Your 11-year old daughter is correct (and the wisdom passed down since the Norman conquest wrong): whenever the home team is batting, the visitors have had more innings.

There are two subtler factors, as discussed here.

(1) The “home field advantage” has less effect in extra innings than in the first nine innings. The reason is simple. Suppose you have a biased coin that flips heads 55% of the time on average. It will flip a majority of heads in nine tosses not with 55% chance but with 62% chance. Similarly the chance that a home field advantage will be decisive over nine innings is much larger than in any single extra inning (or over the 2 or 3 extra innings typical in extra-inning games…

(2) The home team batting in an extra inning has the advantage of knowing what they need. For example, with one runner on they’ll play to sacrifice if the score is tied but not down by two runs. The score will tell them whether to keep their defensive players in, or go all-out with pinch-hitters. The visitors, OTOH, have to guess whether a single run will be enough.

“Winning percentage for all home teams stands at .54175, and in extra innings the home nine performs at .52513.” Effect (1) outwieghs (2); hence the home team wins a smaller percent of extra-inning games as nine-inning games.

9

If you are going into extra innings, then it is not necessarily the case that the home team just needs to score once to win. It is possible that, for instance, the visitors will score three times in the top of the tenth: If that happens, then the home team will need to score at least three times just to keep the game alive, and four to win outright. If that scenario doesn’t come up, then it’s because the home team has prevented it from coming up.

10

That’s it right there.

11

Smart-ass kids these days!

12

I would guess that the middle part of this, the fans rooting for you, would be increased in extra innings. Because your fans are probably local, and can stay later to watch the extra innings. The away team fans are probably not local, and might have to head home sooner.

But given that baseball seems to keep statistics on every single thing, presumably they have an answer for this: do home or away teams win the most in extra-innings games?

13

These effects aren’t limited to extra innings … all this applies to the bottom of the ninth as well.

I always assumed “home field advantage” was based on things like the home team pitcher knowing where the field crew stuck the Vaseline on the pitchers mound, tapping the other teams telecommunications and bugging the dug out and bullpen, and deflating the baseballs for the other teams batters etc etc etc

14

septimus already answered this a couple posts up. Home teams win slightly more in extra-inning games, but at a lower rate than 9-inning games.

15

What the Pirates EARNED were the two ass-whoopings they came away with the following days after making my Dodgers lose a baseball game.

:stuck_out_tongue:

16

I agree that’s an advantage, but it cuts both ways. In the bottom of an extra inning, the defense also knows how many runs are important. For instance, consider the runner on second and one out in a tie game vs three-run game (let’s assume a good batter followed by a weaker one). The batter gets to know how valuable a walk is (probably negative value in the first case, but definitely worthwhile in the second), so they can decide how to approach the at-bat. But, chances are they won’t even get to make that decision because the defense also knows how valuable a walk is and will intentionally walk him in the first case, to set up a potential game-winning double-play.
So both sides get an information advantage. But the defense has a lot of opportunities to make decisions: whether to intentionally walk someone (or semi-intentionally walk by pitching away), whether to bring the infield to double-play depth, whether to throw to the runner on a grounder or take the easy out at first base, whether to play the outfield shallow (one out runner at third), even whether to bother trying to throw out someone stealing second (this happens so often that there’s even a name for it), even whether to make defensive substitutions. In contrast, the offense doesn’t really have many decisions to make: how aggressive to be at the plate, whether to try to steal second, whether to sacrifice, and – occasionally – whether to try and stretch an extra base out of a hit. But these are fewer situations – there’s no term for ‘offensive indifference’ after all.

So, in the end, it seems to me the information advantage should help the away team more.

Though my guess is that the information advantage overall is fairly small and may well be outweighed by the psychological advantage of batting last.

17

I don’t think I saw this mentioned, but another factor that helps the home team is pitcher usage. It’s primarily due to manager’s being short-sighted, but visiting managers rarely use their “closer” (typically their best reliever) in a tied extra inning game - they save them in case their team gets the lead in a the top half of an inning.

Which often leads to the road team using inferior pitchers in extras, while the home team (who will never have a save opportunity) runs their very best out there for the first few extra frames.

18

Possibly more. After the play where the ball went through Buckner’s legs, they still would have been hitting. They could have scored 1, 2, or 10 more runs.

But, dammit, there is still an advantage to only having to score a run instead of scoring a run and getting six outs. I realize that such a scenario means that you have retired the visiting team more times than they have retired you, but, gah! I can’t put my finger on it.

Such a scenario is not merely psychological. It’s right there: 1 run wins. Visiting team must retire six batters and score 1 run.

19

You’re acting like the top of the tenth doesn’t count. The visiting team needs to score one run (in the top of the tenth), then get three outs.

20

But I am looking at it from a particular point in time: the middle of the 10th. The home team clearly has an advantage at that point, right? I’m thinking a Bayes equation might be appropriate.