Pomeroy and Home Court Advantage

[kwyjibo]

Ken Pomeroy's deep off-season dive this year was on the home court advantage (a subject I have discussed here long ago).  The big take away and surprise is that the home court advantage is shrinking and last year the conference home court advantage was only 2.8 points (down from over 4 in 2000).  He does confirm a point I guessed was likely true 10 years ago that whatever home court advantage is it is created by officiating.  He shows that the home court advantage is most correlated with the home foul advantage. Further, as the home foul advantage has declined (video replay used by conferences must be making refs better and fairer) the home court advantage has declined.  The crowd and thus certain atmospheres may play a role in "persuading" refs but there just was not that many consistent places where that was true year over year (of the 50 teams that had the highest HCA in 2002-9, 90% had below average HCA's for 2010-17).  In his data Air Force had the biggest HCA (Texas Tech in his 2002-9 analysis way back) but even that was not that strong.  Given that you have to go through security checkpoints to attend or officiate an Air Force game maybe that is where the refs feel swayed.

https://kenpom.com/blog/how-to-measure-home-court-advantage/

https://kenpom.com/blog/how-to-measure-site-specific-home-court-advantage-part-two/

I know there will be people who still think certain places convey some advantage (or travel) but there does not appear to be any consistent place over 16 years of data that has shown to be a great advantage.  The real story seems to be that officiating has gotten less homer and thus the home court advantage is waning.

[Old guy]

The point that the home court advantage may by primarily due to officiating and that it is shrinking due to increased standardization of ref calls may well be a correct one. However there is always the wear and tear involved in being on the road and how that impacts players in away games. This factor may or may not have much importance after all, but it is always present and has noting to do with officiating decisions.

[Quality Is Job 1]

Part of home-court advantage is also the level of comfort players feel as a result of practicing there every day.

[kshoe]

50 minutes ago, kwyjibo said:

Ken Pomeroy's deep off-season dive this year was on the home court advantage (a subject I have discussed here long ago).  The big take away and surprise is that the home court advantage is shrinking and last year the conference home court advantage was only 2.8 points (down from over 4 in 2000).  He does confirm a point I guessed was likely true 10 years ago that whatever home court advantage is it is created by officiating.  He shows that the home court advantage is most correlated with the home foul advantage. Further, as the home foul advantage has declined (video replay used by conferences must be making refs better and fairer) the home court advantage has declined.  The crowd and thus certain atmospheres may play a role in "persuading" refs but there just was not that many consistent places where that was true year over year (of the 50 teams that had the highest HCA in 2002-9, 90% had below average HCA's for 2010-17).  In his data Air Force had the biggest HCA (Texas Tech in his 2002-9 analysis way back) but even that was not that strong.  Given that you have to go through security checkpoints to attend or officiate an Air Force game maybe that is where the refs feel swayed.

https://kenpom.com/blog/how-to-measure-home-court-advantage/

https://kenpom.com/blog/how-to-measure-site-specific-home-court-advantage-part-two/

I know there will be people who still think certain places convey some advantage (or travel) but there does not appear to be any consistent place over 16 years of data that has shown to be a great advantage.  The real story seems to be that officiating has gotten less homer and thus the home court advantage is waning.

I'd think the Colorado thin air could have an effect on the Air Force advantage too.

Looks like Colorado has the 2nd highest advantage and Colorado St. has the 5th biggest. Seems like that is it, despite a portion of his piece where he says "The increase in samples for the model revealed two other stats of importance: non-steal turnovers and blocks. Home advantages in both of those categories influence the model as well. And finally, a team’s elevation is included in the model."

[kshoe]

SLU's home court advantage over this time period was 4.0 points (27th in the country).

[SShoe]

28 minutes ago, kshoe said:

SLU's home court advantage over this time period was 4.0 points (27th in the country).

Not bad.  Clearly attributable to those in Section 108 who are lobbying the officials on behalf of the team. Because it certainly isn't the students.

[kshoe]

29 minutes ago, SShoe said:

Not bad.  Clearly attributable to those in Section 108 who are lobbying the officials on behalf of the team. Because it certainly isn't the students.

Maybe all the empty seats in the student section contribute to throwing off the opponents.

Even in years when we aren't good, it is interesting that we were 6-3 at home and 1-8 on the road during conference play last year. 

[billikenfan05]

21 hours ago, kshoe said:

Maybe all the empty seats in the student section contribute to throwing off the opponents.

Even in years when we aren't good, it is interesting that we were 6-3 at home and 1-8 on the road during conference play last year. 

I've noted how atrocious we have always (Soderberg-Crews) looked on the road. We just don't play well.

[bonwich]

23 hours ago, kwyjibo said:

Ken Pomeroy's deep off-season dive this year was on the home court advantage (a subject I have discussed here long ago).  The big take away and surprise is that the home court advantage is shrinking and last year the conference home court advantage was only 2.8 points (down from over 4 in 2000).  He does confirm a point I guessed was likely true 10 years ago that whatever home court advantage is it is created by officiating.  He shows that the home court advantage is most correlated with the home foul advantage. Further, as the home foul advantage has declined (video replay used by conferences must be making refs better and fairer) the home court advantage has declined.  The crowd and thus certain atmospheres may play a role in "persuading" refs but there just was not that many consistent places where that was true year over year (of the 50 teams that had the highest HCA in 2002-9, 90% had below average HCA's for 2010-17).  In his data Air Force had the biggest HCA (Texas Tech in his 2002-9 analysis way back) but even that was not that strong.  Given that you have to go through security checkpoints to attend or officiate an Air Force game maybe that is where the refs feel swayed.

https://kenpom.com/blog/how-to-measure-home-court-advantage/

https://kenpom.com/blog/how-to-measure-site-specific-home-court-advantage-part-two/

I know there will be people who still think certain places convey some advantage (or travel) but there does not appear to be any consistent place over 16 years of data that has shown to be a great advantage.  The real story seems to be that officiating has gotten less homer and thus the home court advantage is waning.

One of the guys in my advanced econometrics class (the smartest person in the class, for that matter) did his final project on a model determining the value of home court advantage in the NBA. Remember, this was when you had to enter both the formulae and the data on punch cards. It was quite clever, and the professor (Goldberger of the Klein-Goldberger model, for which Klein won the Nobel) actually laughed out loud for the first time anyone had ever heard him do so. I think the result was "maybe." 

Anyway, said smartest person went on to get his Ph.D. in econometrics. He was, shall we say, a little on the socially defective side and couldn't land a professorial position, so he became a professional gambler, Blackjack, I think. He was eventually banned in virtually every casino in America and many more abroad, but not before he made enough money to retire at age 50. 

The kicker? Despite being from and moving back to San Diego after going to Wisconsin, he sent his kid to SLU. 

[Major Majerus]

After around 45 yrs of SLU home games, I'd say we have the anti home court advantage with the refs.  I can't begin to quantify the WTF moments I've been subjected to by the zebas ... with apologies to Stephan Pastis

[willie]

I believe there is a difference between conference and non- conference games .When we are playing Houston Baptist to start the season Ron Zetcher knows who is supposed to win the game. Scott Thornlee (sp) a big 12 ref would not allow SLU beat Missouri in Columbia.I believe any league ref favors his team when they are out of conference . I acknowledge that most big time officials have many conferences so this doesn't always play. 

[kshoe]

1 hour ago, willie said:

I believe there is a difference between conference and non- conference games .When we are playing Houston Baptist to start the season Ron Zetcher knows who is supposed to win the game. Scott Thornlee (sp) a big 12 ref would not allow SLU beat Missouri in Columbia.I believe any league ref favors his team when they are out of conference . I acknowledge that most big time officials have many conferences so this doesn't always play. 

Generally agree and for what its worth Pomeroy's analysis is only on conference games.

[Quality Is Job 1]

3 hours ago, willie said:

I believe there is a difference between conference and non- conference games .When we are playing Houston Baptist to start the season Ron Zetcher knows who is supposed to win the game. Scott Thornlee (sp) a big 12 ref would not allow SLU beat Missouri in Columbia.I believe any league ref favors his team when they are out of conference . I acknowledge that most big time officials have many conferences so this doesn't always play. 

In games of a reciprocal home series, isn't the officiating crew usually from the visiting team's conference?

[willie]

9 hours ago, Quality Is Job 1 said:

In games of a reciprocal home series, isn't the officiating crew usually from the visiting team's conference?

Not always. Depends on the contract. Seems like the power conferences have their official's  do their games. Buy games certainly not. 

[slu72]

I've always believed home court advantage was due in large part to the following:

1.)Unfamiliarity with the arena. Lighting, court condition, background behind the boards, I think all have an effect on the visitors. As someone pointed out playing in Colorado is definitely a challenge.

2.) Crowd enthusiasm and attitude. I've seen SLU play on the road about fifteen times over the past 20 years and I think they won only one game. I used to go the UC and/or UL games at least once a year when I lived in Ohio. This is when we were back in GMW and CUSA. UL was a tough place, although they did win that game in 2001, UC a little less enthusiastic but still a tough crowd. The one game that stands out is the game at the Dean Dome in Lisch and Lidell's FR year. They actually played the Heels tough until about the last 10 minutes when suddenly the UNC crowd beast woke up and realized they were in a game. I do believe the upped decibel level unsettled the young guys. They also got a few bad calls from the refs in those later minutes.

3.) Length of travel. For anyone who's ever travelled for business on a regular basis it takes it's toll. Airport hassles, hotels, rich restaurant foods, et al makes one weary and longing for the comforts of home. Especially so if travel involves some jet lag. This probably doesn't mean as much to the young men playing hoops, but then again travel does upset their normal campus routines. Add in the fact they now have to find time to study as well when they'd probably rather be out exploring and it takes a toll on their level of concentration.  

4.) A small does of homerism by officials. Refs are only human and can be influenced by volatile home crowds. Still, I think this is minor vs the other 3 factors.

[kwyjibo]

On 9/20/2017 at 3:12 PM, Quality Is Job 1 said:

Part of home-court advantage is also the level of comfort players feel as a result of practicing there every day.

This would be "in theory" measurable in that many teams never practice on their home court (they play games on it though) and some practice on it every day.  If this was significant there should already be evidence of this (although it might just be no one has ever done the work).   "Comfort" should be quantifiable as increased FG percentage but yet there is no evidence of this (once you control for everything else).   If "comfort" translates into fouling less or blocking more than this might be possible.

5 hours ago, slu72 said:

I've always believed home court advantage was due in large part to the following [anecdotes]:

 

 

On 9/20/2017 at 3:01 PM, Old guy said:

The point that the home court advantage may by primarily due to officiating and that it is shrinking due to increased standardization of ref calls may well be a correct one. However there is always the wear and tear involved in being on the road and how that impacts players in away games. This factor may or may not have much importance after all, but it is always present and has noting to do with officiating decisions.

I think everyone who has looked at the HCA understands why travel, crowds, arena characteristics MIGHT be factors that make up the home court advantage.  It has intuitive appeal but the question is how do crowds/arena/travel manifest themselves in real difference on the court.  To say the crowd makes me "feel better" at home or "feel worse" on the road has to be made real in some competitive advantage (some stat).  That is what Pomeroy did--the difference are in fouls called and in non-steal turnovers--both of which are ref driven (there also seems to be a home court block advantage as KShoe notes but in my biased "blocks are overrated" view this just means that blocks are theatrical and no harm in giving the fans a little extra entertainment).

Travel is pretty easy to refute because hard to travel to places do not appear to have any special HCA.  I also think the anecdotes provided for travel underrate the ability and travel experience of college athletes.  There has been some evidence of crossing multiple time zones as a negative factor (and even then it was in one direction, I forget which).

Crowd noise could well be the mechanism by which homer calls are created but there does not appear to be any evidence of that either.  Places in which there are said to be hostile and loud crowds do not seem to have consistently greater HCA.  SLU has had their best home court advantage the last few years and yet crowd size and intensity at SLU is down.  It may be quiet crowds also allow hostile fans to get their zingers in.  It may it is all a wash with noise and refs generally favor the home team slightly regardless of the crowd or how loud they are.

The physical characteristics of the space always had intuitive appeal to me.  It always took me a while to adjust to shooting backgrounds and the first time I ever shot a basketball in a big open arena it was not pretty.  However, I think all these theories underestimate the variety of experience college athletes have these days (they are thankfully not as sheltered as me).

The biggest thing is that Pomeroy's latest work shows that 45 of the top 50 teams from his first 8 year analysis of were below average in the second 8 year analysis.  If crowds/arena/travel were the driving factor then what happened?  Did those teams become easier to travel to?  less intense? more homogenized? 

Also, the HCA is small and getting smaller (4 pts. to 2.8 pts.).  You need to put that into context--there is smaller than the variance in team performance night to night The average difference between predicted result and the actual result in a college basketball are 8-10 points (the best computer models and the betting spreads closer to 8 with the worse models closer to 10).  The home court advantage, even at 2.8pts. is still important but much smaller than other presumably random variations in performance.  Some people may "feel" better playing at home but it would be hard to tell even when they do because the other variations are greater.

The decline of the HCA is the fascinating part.  If it was "comfort" or crowds or travel we would need to know why it was going down (better airplane seats?? I think not!).  Are crowds quieter now (30% less hostile?)?  Are road players adapting better?  Are home players taking their advantage for granted and not using it?  To see the decline of the Home Foul Advantage perfectly track the decline of the Home Court Advantage in Pomeroy's work is powerful evidence (and better than any anecdotes I or others have).

On 9/20/2017 at 3:20 PM, kshoe said:

I'd think the Colorado thin air could have an effect on the Air Force advantage too.

Looks like Colorado has the 2nd highest advantage and Colorado St. has the 5th biggest. Seems like that is it, despite a portion of his piece where he says "The increase in samples for the model revealed two other stats of importance: non-steal turnovers and blocks. Home advantages in both of those categories influence the model as well. And finally, a team’s elevation is included in the model."

You could measure this and it might be a real factor. If those three Colorado schools are all ranked so high I am surprised Pomeroy did not mention it but from your note alone seems hard to argue against.  I know soccer fans argue that altitude gives home teams in South America.  The only issue I would have is that this is from his most recent 8 year data set (using 6 years of data to train the model to explain the other 2 so it really is about very recent HCA and not a long term view) and the most interesting thing from his work is how there does not appear to be much continuity over time.  Lack of continuity gives additional credence to the "mostly refs" view but I would say that from the 1, 2, and 5 ranking alone the altitude may be another factor.   It does not eliminate the possibility the pool of officials working Colorado are unrepentent homers though.

Do not trust Pomeroy?  How about Pitino?  Rick Pitino cited improved refereeing as the driving force in reducing HCA when asked by Seth Davis. “I think the refereeing has gotten much stronger because of television,” Pitino said. “Now, if a ref acts like a homer or makes a mistake, the TV guys will jump on them. That has made them conscious of not being homers. Seven years ago, even five years ago, we didn’t have the use of technology that we have now to show referees their mistakes. . . .These officials are being evaluated so much, the crowd is no longer getting to them. Whereas in the past, if I walked in and saw certain refs on a game, I’d say this is going to a much bigger home court advantage.”   Pitino also said more scouting info was a factor and Seth Davis went on to posit more big HS and AAU games make players adapt to the road better.  I think the data driven approach is much more valid but Pitino seems to agree with the numbers

[brianstl]

Where do other high altitude schools like New Mexico, Wyoming and Nevada rank? 

[Old guy]

There are a number of physiological reasons why athletes habituated to high altitude living can play better at those high altitudes than athletes who live closer to sea level. The higher the altitude the thinner the air becomes, the thinner the air is the less oxygen it carries. Denver air is breathable without oxygen supplementation but being able to breathe and carry on with normal activities does not mean you can engage is strenuous exercise at that altitude and perform like you are accustomed to perform. People that live at high altitude adapt and can perform better than the sea level dwellers because their own bodies respond to the high altitude by making additional hemoglobin and red cells so that their lungs can extract more oxygen form the thinner air, and carry more oxygen to the body than people habituated to life at sea level can do. 

At the time of the Summer Olympics in Mexico City some years ago a number of teams trained for months in Mexico City itself in an attempt to force habituation to the high altitude in their athletes. Personally, I remember getting very short of breath during a meeting I attended many years ago in Reno, NV. No, I was not playing basketball or anything like it but the hotel was pretty high in the mountains and my body was plainly not getting enough oxygen to tolerate much exertion at all. Oh, and I have been to Jackson Hole and the National Parks in Wyoming, also Aspen and Denver CO many times and never got short of breath there.

[kshoe]

1 hour ago, brianstl said:

Where do other high altitude schools like New Mexico, Wyoming and Nevada rank? 

New Mexico is 8th, Wyoming is 10th and Nevada is 87th. Seems pretty conclusive that high altitude is a major factor based on 5 of the top 10 being high altitude schools.