home field advantage/referee bias/ stats, sports, and math

About a month ago, we were having a good discussion about the Steelers/Ravens game, and the officiating. I quoted a Baltimore writer on why the Ravens need to win a home field advantage, citing the referees being influenced by the crowds:

Quote: Mosca

Five Things We Learned in the Ravens 31-24 Loss

5. As admirable as it is that the Ravens can win playoff games on the road, if they want to take the next step toward the Super Bowl, they need to take care of business and get a bye and a home playoff game in 2011.... The Ravens lost this game because they had an epic meltdown on offense in the third quarter, not because of any one call made by the officials. But I do believe emotion and atmosphere play a factor in the way games are officiated, and when the crowd starts going nuts, the officials get caught up that tidal wave of emotion. Studies show it's just a fact. You get more calls at home. That's one reason why you want home playoff games.

Nareed and Wiz, and a couple others, took the opposite view, defending it with some examples:

Quote: Nareed

Quote: Mosca

The officiating was terrible; both teams deserved better, IMO. But as far as favoring one or the other, I think it was about even in badness. Kevin VanValkenberg, writing for Ravens Insider, has a good take on it: you earn the right to have close calls go your way, by winning home field advantage during the regular season.

I don't think the home team gets better calls from the officials, penalty calls or others, but that's beside the point. The point is that a good playoff team will overcome anything and reach the Superbowl. Proof, the Steelers went 3-0 on the road the last time they went to the big game. The Packers may do the same this year.

Of course, usually good playoff teams are also good overall teams. Meaning they play well in the regular season as well as the playoffs. Therefore they tend to have some home games at least. But you also have teams that stink during the playoffs. The old Cleveland Browns, for example (who are now the Ravens, BTW), the Eagles, the Colts and others. No matter how well they do in the season, come playoff time they fall apart, or they lose consistently. There are also teams that play better in the playoffs, like the Steelers, the Jets (this year), the Packers (again, this year) the 80s Broncos (except at the Superbowl), etc.

Quote: Wizard

Here are some statistics from 2000 week to 2010 week 15:

Average away penalties per game: 6.43
Average home penalties per game: 6.04
Average away penalty yards per game: 52.49
Average home penalty yards per game: 49.68

So just a 2.8 penalty yards per game difference in favor of home teams. That knife cuts both ways.

So I looked into this, and I found the book Scorecasting: The Hidden Influences Behind How Sports Are Played and Games Are Won. And within that book is some research... some very, very extensive research. Such as baseball over 100 years, and around the globe. Such as women's sports as well as men's. Games between teams on different coasts, and games between teams in the same cities. Quoting one of the authors from an interview in Wired,

Quote:

Wired.com: So why does the home team win more often?

Wertheim: What’s really interesting is how consistent that truism is. The WNBA has almost the exact same home winning percentage as the NBA. A soccer league in Central America is almost the same as the Premier League. Japanese baseball has almost the same as MLB.

Before you even dig into the “why?” of home-field advantage, you see the data that 100 years ago the home winning percentage in Major League Baseball was almost exactly the same as it is today, and you find the same in other sports.

I think most people think, “Well, you’re playing at home and you’ve got people cheering for you and booing the other the guy,” but we didn’t find that to be the cause. Then you have the theory that home teams get to sleep in their own beds and road teams had to fly in the night before, but that didn’t seem to be the case either.

Wired: Right. You made the point in the book that travel has gotten so much better than 100 years ago, but winning percentage didn’t change from when teams were on buses to now, when they’re taking charters.

Wertheim: Yeah, and in games like when the Angels play the Dodgers or the Ravens play the Redskins — games where there’s negligible travel — the winning percentage stays the same. If you fly across the country, you’re not losing any more than you are when you’re the Chicago White Sox playing across town at Wrigley Field.

So we looked at how games are called and that’s where the data went berserk. Yellow and red cards in soccer, calls in the NFL before and after replay’s implementation, called balls and strikes in baseball — that’s where we saw games are called totally differently based on where they’re played. And the more attended the games are, the more striking the bias. Also, how close the fans are matters. In some European soccer stadiums, the track acts as a moat to keep the fans away and that reduced bias. So everything we found pointed to the home teams winning more because the games are being called differently.

The book is a real eye-opener, in the best way that statistics can be illuminate to human behavior. The authors compile a mountain of data covering a hundred years, hundreds of thousands of games, millions of pitches... they subtract out and allow for other factors... and they conclude things that all of a sudden seem so obvious, but that weren't until you saw the data. Why do more Latin players get caught using steroids, and more US players get caught using marijuana? Why do the Cubs lose? Why is there no "I" in "team", but there is one in "win"? Why is the #1 pick in the NFL draft a curse?




Data culled from 1.1 million pitches shows that umpires will expand the strike zone when there is a 3-ball count on a batter and reduce the strike zone when a batter has two strikes.





For ANYONE who loves sports and numbers... and not just numbers, but how numbers illuminate the world in ways you would have never expected : you will love this book. I read it, and then understood why it is so hard for the Pirates to dig themselves out of their hole (which is another thread entirely.)

I officiate soccer w/ USSF and Ive been lucky enough to do games from minor middle-school age youth home games to major state-wide tournaments...

I dont feel as I ever let the home team or fans influence me other then how I park my car and how close I park to the field. There are times in games, and I think this is where the ball/strike count refers a little is where officials will be more apt to turn one way or another 'for the good of the game'.

Take for example a minor tripping of a player in soccer that occures in the penalty area.. it didnt effect the ball she already kicked it towards the goal and bairly gets stumbled up by the defender... just because the defense player who tripped her was a home team player does not mean I was trying to be nice to the home team.. its because the away team is already leading, the interfearance did not effect the play and the penalty if called would have been a punishment that didnot befit the crime... but what do fans see? "Good non-call ref!" "I cant believe the ref did not call that!! It was a foul!"... for the good of the game guys, for the good of the game.

Quote: Malaru

I officiate soccer w/ USSF and Ive been lucky enough to do games from minor middle-school age youth home games to major state-wide tournaments...

I dont feel as I ever let the home team or fans influence me other then how I park my car and how close I park to the field. There are times in games, and I think this is where the ball/strike count refers a little is where officials will be more apt to turn one way or another 'for the good of the game'.

Take for example a minor tripping of a player in soccer that occures in the penalty area.. it didnt effect the ball she already kicked it towards the goal and bairly gets stumbled up by the defender... just because the defense player who tripped her was a home team player does not mean I was trying to be nice to the home team.. its because the away team is already leading, the interfearance did not effect the play and the penalty if called would have been a punishment that didnot befit the crime... but what do fans see? "Good non-call ref!" "I cant believe the ref did not call that!! It was a foul!"... for the good of the game guys, for the good of the game.

Malaru, the authors in no way indict the officials; in fact, they go out of their way to stress that throughout sports, and especially at the pro level, officials are incredibly accurate, the best they can be. The point they make is that the officials are powerless in the face of the fact that they are humans. They take the examples of their data, and then find other studies showing how human behavior is influenced in the same way, in other parts of life. The biases aren't conscious decisions, but the way people are wired. Read the book and decide.

Nothing can account for the ridiculous fouls called in the NBA. I really enjoy the games despite that, but it still makes me furious.
By the way, the Mavericks have the best play by play guy in the business.

Quite a few years ago, I don't remember exactly when, the 49ers and the Redskins were playing in the NFC championship game. The Niners had been shut out and were losing 21-0 at the beginning of the fourth quarter, when Joe Montana went to work. The 49ers scored three touchdowns in the next eleven minutes and totally took the air out of the Redskins home crowd--you could hear a pin drop. The Redskins got the ball back, and were stuffed on two consecutive plays--then they called a desperation-heave fly pattern on 3rd and 10. The ball wasn't even close to the receiver, and neither was the defender for that matter, but as soon as the ball fell incomplete, the ref threw a flag for "pass interference". The crowd cheered! Two downs later, the exact same situation occured--desperation heave, uncatchable ball, "pass interference". First and 10 on the 49er 9-yard line! How the crowd cheered!

I was watching that, and was appalled at the two horrible calls by an officiating crew that obviously couldn't help but make two hometown decisions so as to restore the rightful winners to their previous place.

Quote: Malaru

I officiate soccer w/ USSF

Nice to see a fellow 'kickball' official! (I used to be in USSF but stopped after a few years at Grade 6, now I only work a handful of High School and NCAA games each season)