In our last installment, we discussed the degree to which past home-scoring advantage predicts future home-scoring advantage. We can look at other stats and derive home advantages from them. For an example, let’s use home steals advantage. Like home-scoring advantage, this is the difference between a team’s home steal margin and road margin.

In conference games from 2002-2009, Alabama averaged 1.32 more steals than their opponents at home and averaged 1.98 fewer steals than their opponents on the road. That gives a home-steals advantage of 1.66, which led all teams during that time.

Does home-steals advantage predict future home-scoring advantage? Well, no, not at all. And most box-score stats don’t. But there is one stat that actually outperforms points. If we just use home-foul advantage by itself to predict future “home-court advantage”, it does significantly better than home-scoring advantage. Here are the predictions compared to the observed values based on using previous home-scoring advantage (HCA) and previous home-foul advantage (HFA).

It’s not a huge difference, but our cloud of data points is getting stretched out along the line of perfect predictions a little bit. Of course, using both home-foul advantage and home-scoring advantage is even better to predict future home-court advantage. The plot on the right below illustrates the predictions of future home-scoring advantage made from such a model.

So it’s pretty clear that fouls drive home-court advantage more than any other thing recorded in the box score.1 Another piece of evidence that foul bias is an important source of home-court advantage is the identical trend in home-court advantage and home-foul advantage2 over the past decade-and-a-half. 

As far as what’s causing the decrease in home-foul advantage, one can only speculate. As officials and their supervisors get more and quicker access to video from games, it stands to reason that they would become more fair about making calls. But it’s also possible that less enthusiastic fan support may be decreasing the home crowd’s influence on officials.3 Or players themselves may be more prepared in road games than they used to be for some reason. Whatever the source, the result appears to be a fairer whistle towards the road team.

The next step is to make predictions for the home-court advantage of each team.  So far, I’ve been using eight years of training data and eight years of target data. It obviously helps to have more seasons to stabilize some of the data, but just using half of our 16-year sample to predict the other half limits us to 325 data points.4 We could use the previous two years to predict the next season of home-court advantage. This has the drawback of increasing the error of predictions, but it has the benefit of increasing our sample by a factor of 15.

After considerable experimentation, I’m using the past six seasons of data for each team to predict its next two season of home-court advantage. This gives the value for each some stability while allowing flexibility for home-court numbers to change over time.

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.

I must warn you that any predictions of team-specific home-court advantage will be noisy. I mean, just look at the plot of predicted vs. actual HCA based on home-foul and home-scoring advantage. A lot of those points stray pretty far from the line of perfect predictions. And those are in-sample predictions. Any predictions for the next few years will undoubtedly be more noisy than that.

The result is that determining which team has the best home-court advantage is impossible with any degree of certainty. Even distinguishing between the tenth-best and 60th-best home-court advantage is on shaky ground. It’s probably best to think of of home-court rankings in groups of three. Teams rated in the top-third probably have an above-average home-court advantage and teams in bottom-third probably have a below average home-court advantage.

Nonetheless, I have posted a team’s home-court advantage computed from this method at the bottom of each team’s schedule. In light of the previous paragraph, the rankings and values are mostly for conversational fodder at your next cocktail party.

Along those lines, the team that currently owns the top ranking in home-court advantage is Air Force, at 4.5 points. An unlikely choice to be sure, and it’s worth repeating that we can never know which team has the best home-court advantage. It is probably not Air Force, a team that plays in a dingy 5,800 seat arena that requires clearing a security checkpoint to get to.

However, it’s illustrative of the fact that home-court advantage and team quality do not have to be related. The Falcons own the second-longest active losing streak in road conference games at 22. And over that time they’ve gone 13-10 in conference games at home. It’s a safe bet they benefit from an above-average home-court advantage.

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1. This is largely consistent with findings offered by Tobias Moskowitz and Jon Wertheim in the book Scorecasting: The Hidden Influences Behind How Sports Are Played and Games Are Won.
2. It’s important to note that a team’s home-foul advantage is not simply how many fewer fouls that team commits at home compared to its opponents. It’s the team’s foul difference at home relative to its foul difference on the road.
3. There’s another question about what drives home-foul bias and given that teams from better conferences tend to benefit from home-foul advantage the most, one could infer that the crowd has a significant influence on this.
4. Additionally, a team’s home-court advantage is probably not constant over an eight-year period.

Who has the largest home-court advantage in college basketball? How many points is it worth? Well, I have some bad news for you: It is really impossible to answer these questions with much precision. We can look at the box score of a game and see how many points a team won by or how many points each player scored.

Maybe one could do a little more fancy maths and make an estimate on what each player contributed to the point total. But we can’t tell how many points the home court contributed. Maybe someday, but for the most part people don’t care as much about the value of home-court as they do about the value of a star player. So that’s where the research focus lies.

But it’s a fun analytic exercise to try determine the value of home-court. I’ve been thinking about it for a while, starting a few years ago I wrote this article about home-court advantage at ESPN. The analysis was rather primitive and I apologize to everyone for paying their hard-earned Insider money for that. Basically, it identified the teams that had the largest difference between their home and road scoring-margin in conference play. Those teams probably had the largest home-court advantage, right?

For instance, from 2002-2009, Texas Tech outscored its opponents by an average of 6.0 points in conference games in Lubbock and were outscored by 9.3 points per conference game on the road. The difference of 15.3 suggests a home-court advantage of 7.6 points per game relative to a neutral court. That figure was the highest among 320 teams that played at least 50 conference games over that time. (more…)

There is one final obligation to tend to before the books can be closed on the 2017 season and that is the revealing of the 2017 kenpom.com player of the year. This season’s honoree is Villanova’s Josh Hart who closed out a distinguished four-year run at Villanova in style.

This season, Hart posted a 122 offensive rating with a 27% usage rate, which included making 40% of his three’s and 58% of his two’s. He had just five games this season where his offensive rating was below 100. Along the way to leading Villanova to its fourth-consecutive solo Big East regular season title, he also posted career-highs in steal rate and assist rate. (more…)

There were 1,930 games between Division-I teams in February and March. Here are the wildest things that happened during the months:

Biggest Upsets

[Tournament games only] March 2: #305 Campbell 81, #98 UNC Asheville 79 (OT) (11.7%) The biggest upset of single-elimination basketball was the seven-seed over the two-seed in Big South quarterfinal action. But the story of this game was Campbell’s Chris Clemons. He’s 5-9, occasionally dunks, and scored 51 points in this game. He led the nation by taking 42% of his team’s shots when on the floor, and he used an incredible 53% of the Camels’ possessions in this game. Normally, that’s the hallmark of a senior going rogue in some sort of Kobe-like farewell game.

But Clemons is a sophomore and was quite efficient in this performance, committing just three turnovers while going 18-of-32 from the field which included eight 3-pointers. Campbell’s eventually appearance in the Big South title game was the second least-likely team accomplishment in conference tournament action, given a 3.6% chance of happening before action began.

2. February 27: #323 Savannah State 74, #141 N.C. Central 73 (5.9%) I’m not sure what’s in store for Savannah State next season, but in the Tigers’ penultimate game of the season, they recorded their most impressive performance, a road win against the regular-season champs of the MEAC. Weirdly, it was the most conventional game the team played all season. They took an unremarkable number of 3’s (26) and played just 70 possessions of basketball, equalling their slowest-paced game of the season.  (more…)

Hey coaches, my offer for scheduling help is back for a second season. I can provide you a spreadsheet with a first cut of expected ratings for every team next season which will include a list of all 351 D-I teams with overall ranking, and national rankings in offense, defense, and tempo. It will be updated every two weeks with the latest roster changes around the country. The projections are mostly based on the quality of returning players, transfers, and previous team performance, but there is more discussion about the ingredients here.

In addition, for those of you that are into gaming the RPI, teams are also ranked by projected conference winning percentage so you can identify opponents which may rack up plenty of wins but are relatively easy to defeat. This data can assist you in finding the type and quality of opponent you are looking for to fill out your schedule for the upcoming season and will not be shared with anyone outside the coaching community until October. Please send a message to ratings at kenpom dot com and we can discuss terms.

Some say it’s too early to do this. Others say it’s too late. Someday, people will produce living, breathing projections for the following season that update with every personnel move of the offseason and nobody will think anything of it. I am not doing that yet, at least not publicly. But for now it’s time to reveal my computer’s early top ten for next season. I hope you enjoy it.

This is completely automated based on the algorithm used to produce last season’s pre-season ratings. My computer has no particular love for hate for any entity composed of human beings, except for the Maryland Terrapins’ basketball team. It also surely has a few blind spots. That said, the computers did a nice job this season. When people say Baylor didn’t get any preseason AP votes, well, the computers voted for them! So maybe you shouldn’t ignore the computers or dismiss their output when it disagrees with your own thinking.

That said, you shouldn’t ignore people’s predictions, either. Just pay attention to everything basically. Computers and (credible) people can help each other make better predictions. (more…)

The group of 16-seeds aren’t particularly strong this season, so it’s tough to get too excited about the possibility of a one-seed losing its first game. (The best chance for it will easily be NC Central against Kansas should it happen.) But if a 16-seed is really, truly serious about beating a one-seed, it should look to Ty Lawson for a tool to use in its mission.

You may recall Lawson’s move in a game against Denver on February 24. (more…)

Here are the chances each team makes it to each round based on my current ratings. Go Zags?

                             Rd2   Swt16  Elite8 Final4 Final  Champ
 1W  Gonzaga                 98.5   83.9   60.2   45.4   29.6   20.5
 1E  Villanova               96.8   70.2   43.4   28.3   16.0   10.0
 1S  North Carolina          98.0   78.6   57.3   33.3   19.9    9.9
 2S  Kentucky                95.6   56.2   36.1   21.0   12.2    5.8
 1MW Kansas                  95.3   69.1   41.1   22.8   11.7    5.2
 2MW Louisville              93.4   56.4   35.5   20.5   11.0    5.1
 4W  West Virginia           87.9   60.6   24.7   15.3    7.8    4.2
10S  Wichita St.             75.0   37.3   22.9   12.8    7.1    3.3
 2E  Duke                    91.7   62.9   33.5   15.0    6.5    3.2
 4E  Florida                 82.9   46.7   22.0   12.3    5.7    3.0
 5E  Virginia                78.5   43.5   20.9   11.6    5.5    2.9
 3MW Oregon                  89.4   57.2   27.5   13.9    6.4    2.6
 3E  Baylor                  84.1   46.9   26.5   11.9    5.2    2.5
 6E  SMU                     76.7   42.9   24.4   11.0    4.9    2.4
 4MW Purdue                  76.8   45.3   24.0   12.3    5.8    2.4
 7W  Saint Mary's            71.0   40.3   24.6    9.8    4.5    2.2
 3S  UCLA                    92.2   52.3   21.6   10.3    4.9    1.8
 3W  Florida St.             86.3   59.1   29.9   10.1    4.1    1.8
 2W  Arizona                 92.5   48.9   28.2    9.8    4.0    1.8
 5MW Iowa St.                73.1   39.2   19.7    9.6    4.3    1.7
 4S  Butler                  84.3   52.2   20.9    8.5    3.6    1.2
 6S  Cincinnati              61.3   31.5   12.7    5.9    2.7    1.0
 7MW Michigan                51.3   22.5   11.9    5.6    2.5    1.0
10MW Oklahoma St.            48.7   20.3   10.7    5.1    2.1    0.8
 8E  Wisconsin               66.5   22.7   10.0    4.8    1.8    0.8
 5W  Notre Dame              68.7   28.3    8.3    4.0    1.5    0.6
 6MW Creighton               59.8   26.5    9.9    4.0    1.4    0.4
 8MW Miami FL                54.3   17.5    6.8    2.4    0.8    0.2
 5S  Minnesota               54.3   24.7    7.3    2.2    0.7    0.2
10E  Marquette               51.2   18.5    6.7    1.9    0.5    0.1
 7E  South Carolina          48.8   17.1    6.1    1.7    0.4    0.1
11W  Xavier                  51.3   19.4    6.7    1.4    0.4    0.1
 8S  Arkansas                54.1   12.1    5.3    1.5    0.4    0.1
11MW Rhode Island            40.2   14.5    4.3    1.4    0.4    0.1
12S  Middle Tennessee        45.7   19.2    5.2    1.4    0.4    0.1
 9MW Michigan St.            45.7   12.5    4.2    1.3    0.4    0.08
11S  Kansas St.              19.9    7.9    2.3    0.8    0.3    0.08
 9W  Vanderbilt              51.5    8.3    2.8    1.1    0.3    0.08
 6W  Maryland                48.7   17.8    6.0    1.1    0.3    0.07
 8W  Northwestern            48.5    7.5    2.4    0.9    0.2    0.07
11S  Wake Forest             18.9    7.3    2.0    0.7    0.2    0.06
 7S  Dayton                  25.0    6.1    2.2    0.7    0.2    0.04
 9S  Seton Hall              45.9    9.1    3.6    0.9    0.3    0.04
10W  VCU                     29.0   10.1    3.9    0.7    0.2    0.04
 9E  Virginia Tech           33.5    6.7    1.9    0.6    0.1    0.04
12MW Nevada                  26.9    8.3    2.3    0.6    0.1    0.02
13MW Vermont                 23.2    7.2    1.9    0.4    0.1    0.02
12W  Princeton               31.3    7.7    1.2    0.4    0.1    0.02
11E  Providence              12.5    3.8    1.1    0.2    0.05   0.01
12E  UNC Wilmington          21.5    5.3    1.0    0.2    0.05   0.007
13E  East Tennessee St.      17.1    4.5    0.8    0.2    0.03   0.007
11E  USC                     10.8    3.2    0.9    0.2    0.03   0.005
13W  Bucknell                12.1    3.4    0.4    0.08   0.01   0.003
14W  Florida Gulf Coast      13.7    3.8    0.7    0.05   0.009  0.002
14E  New Mexico St.          15.9    3.2    0.6    0.08   0.007  0.001
13S  Winthrop                15.7    3.8    0.4    0.04   0.004  0.001
14MW Iona                    10.6    1.9    0.2    0.03   0.002  <.001
15MW Jacksonville St.         6.6    0.8    0.1    0.01   0.002  <.001
15E  Troy                     8.3    1.5    0.2    0.02   <.001  <.001
16MW North Carolina Central   3.8    0.8    0.09   0.007  <.001  <.001
14S  Kent St.                 7.8    1.0    0.07   0.005  <.001  <.001
15W  North Dakota             7.5    0.8    0.09   0.003  <.001  <.001
15S  Northern Kentucky        4.4    0.4    0.04   0.003  <.001  <.001
16E  New Orleans              2.3    0.3    0.03   0.003  <.001  <.001
16S  Texas Southern           2.0    0.3    0.03   <.001  <.001  <.001
16W  South Dakota St.         1.5    0.2    0.02   <.001  <.001  <.001
16E  Mount St. Mary's         1.0    0.08   0.005  <.001  <.001  <.001
16MW UC Davis                 0.9    0.1    0.005  <.001  <.001  <.001

                             Rd2   Swt16  Elite8 Final4 Final  Champ
 1W  Gonzaga                 98.5   83.9   60.2   45.4   29.6   20.5   
 4W  West Virginia           87.9   60.6   24.7   15.3    7.8    4.2   
 7W  Saint Mary's            71.0   40.3   24.6    9.8    4.5    2.2
 3W  Florida St.             86.3   59.1   29.9   10.1    4.1    1.8   
 2W  Arizona                 92.5   48.9   28.2    9.8    4.0    1.8   
 5W  Notre Dame              68.7   28.3    8.3    4.0    1.5    0.6   
11W  Xavier                  51.3   19.4    6.7    1.4    0.4    0.1   
 9W  Vanderbilt              51.5    8.3    2.8    1.1    0.3    0.08  
 6W  Maryland                48.7   17.8    6.0    1.1    0.3    0.07  
 8W  Northwestern            48.5    7.5    2.4    0.9    0.2    0.07  
10W  VCU                     29.0   10.1    3.9    0.7    0.2    0.04  
12W  Princeton               31.3    7.7    1.2    0.4    0.1    0.02  
13W  Bucknell                12.1    3.4    0.4    0.08   0.01   0.003 
14W  Florida Gulf Coast      13.7    3.8    0.7    0.05   0.009  0.002 
15W  North Dakota             7.5    0.8    0.09   0.003  <.001  <.001 
16W  South Dakota St.         1.5    0.2    0.02   <.001  <.001  <.001 

                             Rd2   Swt16  Elite8 Final4 Final  Champ
 1E  Villanova               96.8   70.2   43.4   28.3   16.0   10.0   
 2E  Duke                    91.7   62.9   33.5   15.0    6.5    3.2   
 4E  Florida                 82.9   46.7   22.0   12.3    5.7    3.0   
 5E  Virginia                78.5   43.5   20.9   11.6    5.5    2.9   
 3E  Baylor                  84.1   46.9   26.5   11.9    5.2    2.5   
 6E  SMU                     76.7   42.9   24.4   11.0    4.9    2.4   
 8E  Wisconsin               66.5   22.7   10.0    4.8    1.8    0.8   
10E  Marquette               51.2   18.5    6.7    1.9    0.5    0.1   
 7E  South Carolina          48.8   17.1    6.1    1.7    0.4    0.1   
 9E  Virginia Tech           33.5    6.7    1.9    0.6    0.1    0.04  
11E  Providence              12.5    3.8    1.1    0.2    0.05   0.01  
12E  UNC Wilmington          21.5    5.3    1.0    0.2    0.05   0.007 
13E  East Tennessee St.      17.1    4.5    0.8    0.2    0.03   0.007 
11E  USC                     10.8    3.2    0.9    0.2    0.03   0.005 
14E  New Mexico St.          15.9    3.2    0.6    0.08   0.007  0.001 
15E  Troy                     8.3    1.5    0.2    0.02   <.001  <.001 
16E  New Orleans              2.3    0.3    0.03   0.003  <.001  <.001 
16E  Mount St. Mary's         1.0    0.08   0.005  <.001  <.001  <.001 


                             Rd2   Swt16  Elite8 Final4 Final  Champ
 1S  North Carolina          98.0   78.6   57.3   33.3   19.9    9.9   
 2S  Kentucky                95.6   56.2   36.1   21.0   12.2    5.8   
10S  Wichita St.             75.0   37.3   22.9   12.8    7.1    3.3   
 3S  UCLA                    92.2   52.3   21.6   10.3    4.9    1.8   
 4S  Butler                  84.3   52.2   20.9    8.5    3.6    1.2   
 6S  Cincinnati              61.3   31.5   12.7    5.9    2.7    1.0   
 5S  Minnesota               54.3   24.7    7.3    2.2    0.7    0.2   
 8S  Arkansas                54.1   12.1    5.3    1.5    0.4    0.1   
12S  Middle Tennessee        45.7   19.2    5.2    1.4    0.4    0.1  
11S  Kansas St.              19.9    7.9    2.3    0.8    0.3    0.08  
11S  Wake Forest             18.9    7.3    2.0    0.7    0.2    0.06  
 7S  Dayton                  25.0    6.1    2.2    0.7    0.2    0.04  
 9S  Seton Hall              45.9    9.1    3.6    0.9    0.3    0.04  
13S  Winthrop                15.7    3.8    0.4    0.04   0.004  0.001 
14S  Kent St.                 7.8    1.0    0.07   0.005  <.001  <.001 
15S  Northern Kentucky        4.4    0.4    0.04   0.003  <.001  <.001 
16S  Texas Southern           2.0    0.3    0.03   <.001  <.001  <.001 
 
                             Rd2   Swt16  Elite8 Final4 Final  Champ
 1MW Kansas                  95.3   69.1   41.1   22.8   11.7    5.2   
 2MW Louisville              93.4   56.4   35.5   20.5   11.0    5.1   
 3MW Oregon                  89.4   57.2   27.5   13.9    6.4    2.6   
 4MW Purdue                  76.8   45.3   24.0   12.3    5.8    2.4   
 5MW Iowa St.                73.1   39.2   19.7    9.6    4.3    1.7   
 7MW Michigan                51.3   22.5   11.9    5.6    2.5    1.0   
10MW Oklahoma St.            48.7   20.3   10.7    5.1    2.1    0.8   
 6MW Creighton               59.8   26.5    9.9    4.0    1.4    0.4   
 8MW Miami FL                54.3   17.5    6.8    2.4    0.8    0.2   
11MW Rhode Island            40.2   14.5    4.3    1.4    0.4    0.1  
 9MW Michigan St.            45.7   12.5    4.2    1.3    0.4    0.08  
12MW Nevada                  26.9    8.3    2.3    0.6    0.1    0.02  
13MW Vermont                 23.2    7.2    1.9    0.4    0.1    0.02  
14MW Iona                    10.6    1.9    0.2    0.03   0.002  <.001 
15MW Jacksonville St.         6.6    0.8    0.1    0.01   0.002  <.001 
16MW North Carolina Central   3.8    0.8    0.09   0.007  <.001  <.001 
16MW UC Davis                 0.9    0.1    0.005  <.001  <.001  <.001

Ivy League (conference rank: 17th)
March 11-12
All games at Penn.
kPOY: Steven Cook, Princeton
Regular season champ: Princeton (preseason #36 / 1st Ivy, current #61)
Overachiever: Penn (preseason #231, current #163)
Underachiever: Dartmouth (preseason #216, current #304)

The Ivy League debuts a real tournament this season and as it turns out, the league’s braintrust picked the exact worst format to be fair to the conference champ. The Ivy is planning to go with a four-team neutral-site event. But it’s not too late back out! According to league bylaw 1.b.14.0x2D, Ivy League executive director Robin Harris can do whatever the heck she wants in an emergency. And this is the emergency: Princeton, who went unbeaten and won the league by four games, is getting screwed.

It sounds great in principle for the Ivy to limit the field to half the teams. Preserving the sanctity of the regular season and all that. But in practice, Princeton has to play its first game on its opponent’s home floor. This is the main reason that the Tigers are more likely than not to end up in the NIT this season. Any other reasonable format the Ivy chose would give Princeton at least a marginally-better chance at a title.

A full-field neutral site event would mean the 2, 3, and 4 seeds would be less likely to end up in the semis than Princeton, who would draw #304 Dartmouth in a quarterfinal game. Or the Ivy could have gone with a double stepladder bracket used by the OVC and the Southland and that would marginally improve Princeton’s chances as well.

But neither of those formats would push Princeton over the 50% mark. The ultimate bracket would use the home-court format with reseeding after the quarterfinals. That would give Princeton about a 2-in-3 chance of a title. And if the Ivy isn’t interested in holding a tournament to get all of its member teams together in the same spot, then why not go with the format that gives its regular-season champ the best shot at winning?

              Final Champ
 1 Princeton   66.1  45.2
 2 Harvard     59.4  24.2
 4 Penn        33.9  17.5
 3 Yale        40.6  13.1

Western Athletic Conference (conference rank: 21st)
March 9-11
All games at Las Vegas.
kPOY: Dewayne Russell, Grand Canyon
Regular season champ: Cal State Bakersfield (preseason #129 / 1st WAC, current #110)
Overachiever: Utah Valley (preseason #321, current #196)
Underachiever: Chicago State (preseason #339, current #339)

It was just two seasons ago that the WAC was ranked 31st among conferences. But things are changing. Cal State Bakersfield has put together back-to-back solid seasons under Rod Barnes. New Mexico State navigated a coaching change as well as one could expect. And potential doormats UTRGV and Utah Valley showed signs of life this season. For at least one season, the WAC has bragging rights on the Big West. (more…)