Replacement Referees and Home Field Advantage: It’s Been Almost Eight Points a Game Through Two Week

[denverYooper]

Or "Lies, damned lies, and Statistics"

http://www.thebiglead.com/index.php/2012/09/19/replacement-referees-and-home-field-advantage-its-been-almost-eight-points-through-two-weeks/

I thought this was interesting but overblown. The nugget about penalties, linked from another site was interesting:

Last week, I hinted that there may be a bias by the officials in favor of the home team, as these less-experienced referees may be more likely to side with the voices of the crowd. That hypotheses certainly wasn’t disproved this week, as 14 of the 16 home teams won, the first time 14 home teams have won in a week since the league expanded to 32 teams. So far this season, there have been 231 penalties against visiting teams and only 188 penalties against the hosts. That ratio — road teams having to deal with 23% more penalties — is far out of line with historical data, which informs us that road teams had 7% more penalties enforced against them than home teams from 2000 to 2011.

BUT

He then goes on to claim that the replacement refs are giving a home team advantage of 8 points throughout the first two weeks. His main reason for that claim:

Here is the against the spread records and median points above or below the spread for the home team:

2012: 19-13 against the spread, +5.3 points over spread for home team
2011: 16-15-1 against the spread, +1.5 points over spread for home team
2010: 19-11-2 against the spread, +3.8 points over spread for home team
2009: 12-20 against the spread, -4.8 points under spread for home team
Combining all three previous years, we get a home team ATS record of 47-46-3, with a median result of a push. So basically, Vegas has been dead on with variation from year over year. Maybe this year is just another case of random variation, though I think there are legitimate reasons to think that it is more than that.

So far, in order to get an even betting result of point spread wins by home teams and road teams, Vegas would have had to add a whopping 5.3 points to each spread to the home team’s line. They already build in somewhere around 2.5 to 3 points for home field in matchups, meaning Vegas would have had to add about 8 points to home field to even out the replacement referee results.

My issues with this analysis are a couple:
1.) It's a little weird that he takes the mean of yearly medians but it gets him to where he wants to go: a mean of 0 (0.17) before this year.
2.) The variability of just that small, questionably constructed, data set is huge. The standard deviation is 4.45 which means that 5.3 points above the spread is not that crazy. Given his data, it would happen like 12.5% of the time. I mean, that's smallish but not significant in any statistical sense.

I read it a couple of times to see whether he was just saying that homefield advantage is 8 points currently or whether he was saying that the replacement refs were causing an 8 point homefield advantage. It's pretty clear to me that he's at least trying to imply to people that the latter is the case.

LIS, I think this is interesting and there is an effect but I think the article is pretty far off on the magnitude of that effect.

[Fritz]

Shit dude, that's some tight analysis on your part. Go you! I like it!=D

[Guiness]

I think it's very likely that the replacement refs could be influenced by a vocal home crowd. I saw an article which claimed Ray Lewis intimidated a referee into making a call.

How are you calculating std dev? Each week as a data point and the amount over/under the spread for each week as the difference from the mean?

I think it's a pretty significant value, and I'm sure Vegas has some Actuarial Science guys pouring over it right now!

[pbmax]

My concern is that refs are so slow to make a call (and it seems they all are, even the groups that seem under control) and throw such late flags, that it is subjecting them to more pressure than if they simply decided earlier. If you are hemming and hawing about a call, the screams in your ear are not going to help and might provoke a specific action.

[Harlan Huckleby]

I don't give a damn if they get all the calls right. They blow only a few more than the experienced refs. The problem is that the games are slow and boring.


One factor that I think is overlooked is that the refs are going through a learning curve, and they will get better as season goes along. So the bargaining position is all with the owners.

[HarveyWallbangers]

I tend to agree with Harlan. The old refs blew a lot of calls, but these new refs slow the game down so much. ESPN posted something where it showed the new refs are calling the almost identical number of overall penalties, almost identical number of pass interferences (even though Percy Harvin complained about an obvious offensive pass interference that was call on him), almost identical number of holdings, etc. And an almost identical number of plays have been overturned. I thought the refs were brutal in the first Packers game and decent in the second game. (They missed some holding calls, but the old refs had crews that would call games a certain way.) Similar thing in the preseason. Some of these crews are doing a pretty good job. Coming from somebody who has experience as an official (and was pretty good at the level he officiated), officials aren't like athletes. There are a limited number of people on earth who are good enough to play in the NFL. There are a lot of people who could officiate sports at a high level if they were willing to foresake more lucrative careers and had the time to concentrate on it. I would've continued officiating if the pay wasn't so shitty at the lower levels and the avenues to get to the top weren't so narrow. There are plenty of people capable of officiating at a high level. It isn't rocket surgery. I'd prefer the old refs, but the old refs aren't irreplaceable. However, these new guys need to get better in a hurry. If the old refs aren't back, I'm hoping these new guys get caught by playoff time.

[Guiness]

I tend to agree with Harlan. The old refs blew a lot of calls, but these new refs slow the game down so much. ESPN posted something where it showed the new refs are calling the almost identical number of overall penalties, almost identical number of pass interferences (even though Percy Harvin complained about an obvious offensive pass interference that was call on him), almost identical number of holdings, etc. And an almost identical number of plays have been overturned. I thought the refs were brutal in the first Packers game and decent in the second game. (They missed some holding calls, but the old refs had crews that would call games a certain way.) Similar thing in the preseason. Some of these crews are doing a pretty good job. Coming from somebody who has experience as an official (and was pretty good at the level he officiated), officials aren't like athletes. There are a limited number of people on earth who are good enough to play in the NFL. There are a lot of people who could officiate sports at a high level if they were willing to foresake more lucrative careers and had the time to concentrate on it. I would've continued officiating if the pay wasn't so shitty at the lower levels and the avenues to get to the top weren't so narrow. There are plenty of people capable of officiating at a high level. It isn't rocket surgery. I'd prefer the old refs, but the old refs aren't irreplaceable. However, these new guys need to get better in a hurry. If the old refs aren't back, I'm hoping these new guys get caught by playoff time.

Right on point there. It's mostly just a learning curve. Hockey linesmen are an exception to the thought everyone can do it though - you have to be fast to keep up with the play for offsides, and strong to get in the middle of fights. Referees get pudgy, but the linesmen are fit. Unfortunately, like other sports, the pay on the way up sucks, although it kept me in beer money in University.

[Joemailman]

I think we know why the NFL moved the 3:15 games to 3:25. The game is definitely getting slowed down. However, because the NFL reviews all scoring plays, and all turnover plays, the odds are against the outcome of a game obviously turning due to a bad call. The old refs need to make a deal and get back, because they don't have much leverage. Steve Young was right. Fans may complain about the replacement refs, but they won't stop watching or going to the games. As long as the money keeps pouring in, the owners don't really care that much who the refs are.

[pbmax]

I tend to agree with Harlan. The old refs blew a lot of calls, but these new refs slow the game down so much. ESPN posted something where it showed the new refs are calling the almost identical number of overall penalties, almost identical number of pass interferences (even though Percy Harvin complained about an obvious offensive pass interference that was call on him), almost identical number of holdings, etc. And an almost identical number of plays have been overturned. I thought the refs were brutal in the first Packers game and decent in the second game. (They missed some holding calls, but the old refs had crews that would call games a certain way.) Similar thing in the preseason. Some of these crews are doing a pretty good job. Coming from somebody who has experience as an official (and was pretty good at the level he officiated), officials aren't like athletes. There are a limited number of people on earth who are good enough to play in the NFL. There are a lot of people who could officiate sports at a high level if they were willing to foresake more lucrative careers and had the time to concentrate on it. I would've continued officiating if the pay wasn't so shitty at the lower levels and the avenues to get to the top weren't so narrow. There are plenty of people capable of officiating at a high level. It isn't rocket surgery. I'd prefer the old refs, but the old refs aren't irreplaceable. However, these new guys need to get better in a hurry. If the old refs aren't back, I'm hoping these new guys get caught by playoff time.

Not sure about identical calls. I read somewhere that Pass Interference was up but Illegal Contacts were down. The reasoning of a former ref was that most people can identify pass interference across levels of the sport. However, illegal contact in the NFL is far more restrictive on DBs and no one can know the ins and outs of it in two months.

But its possible we simply don't have enough data to be sure. Two games is a small sample with new refs.

I disagree with Harlan that they are in the same ballpark of blown calls. As in the Eagles-Ravens game, when they call a penalty, its often the wrong one and yardage is then off. Not to mention the 11 yard markoff on a 5 yard penalty they had.

The more troubling aspect is that the officials have not asserted themselves and players and coaches are taking advantage of them. Its very chippy out there and eventually its going to result in a fight and someone (quite possibly a ref) getting hurt. If I was a crew chief, I'd toss the first player who barked at one of the refs right away.

[mraynrand]

If I was a crew chief, I'd toss the first player who barked at one of the refs right away.

There goes Peyton Manning

[mraynrand]

I would just call penalties on everyone and let God sort it out.

[mraynrand]

Or "Lies, damned lies, and Statistics"

http://www.thebiglead.com/index.php/2012/09/19/replacement-referees-and-home-field-advantage-its-been-almost-eight-points-through-two-weeks/

I thought this was interesting but overblown. The nugget about penalties, linked from another site was interesting:



BUT

He then goes on to claim that the replacement refs are giving a home team advantage of 8 points throughout the first two weeks. His main reason for that claim:



My issues with this analysis are a couple:
1.) It's a little weird that he takes the mean of yearly medians but it gets him to where he wants to go: a mean of 0 (0.17) before this year.
2.) The variability of just that small, questionably constructed, data set is huge. The standard deviation is 4.45 which means that 5.3 points above the spread is not that crazy. Given his data, it would happen like 12.5% of the time. I mean, that's smallish but not significant in any statistical sense.

I read it a couple of times to see whether he was just saying that homefield advantage is 8 points currently or whether he was saying that the replacement refs were causing an 8 point homefield advantage. It's pretty clear to me that he's at least trying to imply to people that the latter is the case.

LIS, I think this is interesting and there is an effect but I think the article is pretty far off on the magnitude of that effect.

The p value on the ANOVA is greater than 0.5. Nothing to see here.

[pbmax]

There goes Peyton Manning

That would deliver two messages. One to the players about everyone being accountable. Two, the message the League office sends you about your termination.

[Harlan Huckleby]

It isn't rocket surgery.

True, but nothing really is.

[denverYooper]

I think it's very likely that the replacement refs could be influenced by a vocal home crowd. I saw an article which claimed Ray Lewis intimidated a referee into making a call.

How are you calculating std dev? Each week as a data point and the amount over/under the spread for each week as the difference from the mean?

I think it's a pretty significant value, and I'm sure Vegas has some Actuarial Science guys pouring over it right now!

For the purpose of commenting on the numbers he used, I calculated the std dev based on the median pts from spread data that he listed in the article. He used those numbers to base his argument that "over these last 3 years, the average (of the median points above spread) is basically flat. Which was true, but the numbers he used were flung about that mean pretty far. He apparently used the spread data from the goldline link he provided but when I clicked on it to find his base data, it just sent me to the front page of a betting site and I just didn't have time to find the base data. It would be more informative to dig around there to get the full game by game spreads and difference.

You're right though, there is probably something going on. Just not 8 points' worth. Gun to my head, I'd guess 1-2 pts.