The Dance Card

As the season winds down, discussions of the NCAA tourney bubble will surely heat up. Talking heads will guarantee that 75 different teams are “in�. Terms like quality wins, bad losses, finishing strong, and stumbling down the stretch will be daily discussion points on the internet and in the main-stream media.

Past experience has led me to conclude that a good percentage of what I read or hear is not worth the time it consumes. But when I was searching for articles on the NCAA Selection Committee, I stumbled upon something far different than the normal silly chatter or bracketology.

Two professors and self-professed basketball addicts performed a parametric study to develop a formula that predicts which teams will receive at-large bids to the NCAA tourney. They called their formula “The Dance Card� and appear to be updating their ranking on a weekly basis. Here is a short overview:

Accuracy of the Dance Card
The Dance Card has never missed on more than three spots in any season. Over the entire 12-year period, the Dance Card correctly predicted 385 of the 410 available at-large Tournament slots (or 93.9%)…

The Dance Card can only be as accurate as the Selection Committees are consistent; it is an estimate of the Selection Committees’ (not the authors’) decision criteria. The high level of accuracy and consistency of the model is strong evidence that the Selection Committees (which differ in composition each year) are actually quite consistent from year to year.

Description of the Dance Card
…The Dance Card formula suggests that only six pieces of information about each team are highly important in determining whether it gets an at-large Tournament bid:

– RPI (Ratings Percentage Index) Rank
– Conference RPI Rank
– Number of wins against teams ranked from 1-25 in RPI
– Difference in number of wins and losses in the conference
– Difference in number of wins and losses against teams ranked 26-50 in RPI
– Difference in number of wins and losses against teams ranked 51-100 in RPI

-Interesting Side Note: The Dance Card did not predict NC State’s selection in 2003 or 2005 (using the new RPI formula). Using the old RPI formula, the Dance Card would have predicted NC State to receive an at-large bid in 2005. The authors have decided to use the old RPI formula for this year’s Dance Card since it appears that the Selection Committee did not really use the new formula last year.

If we assume that the Dance Card authors’ have discovered the key parameters used by the Selection Committee, then there are several items worthy of discussion.

STRENGTH OF SCHEDULE
I find it interesting that the conference RPI rank shows a correlation and the individual team’s strength of schedule apparently does not. When you consider that the larger conferences (conference size not just strength) play a un-balanced schedule, it would appear that the Selection Committee would be giving some teams more credit and others less credit than they deserve.

Before we get into a large rant on this point, it is important to remember that the overall schedule strength is inherently included in the RPI calculation. But then again, the conference strength is inherently included as well. I just found it strange that conference strength by itself turned out to be an important factor.

RECORD OVER THE LAST 10 GAMES
I am almost sure that I have read articles where the Selection Committee specifically said that this was a consideration. However, the Dance Card Authors apparently couldn’t find any evidence to support this claim. To double-check the Dance Card formula, I scanned down through the NCAA Bubble Teams (RPI #36 through last team in) to see what I could find.

Finishing Strong
To supplement the Dance Card’s conclusions, if I could find “major� schools with strong finishes, “reasonable� RPI rankings, and in the NIT….then it would pretty well prove that finishing strong is not necessarily enough to impress the Selection Committee. Here are some examples of teams that fell into the NIT:

 

 

 

 

 

W/L over

Year

RPI

SOS

Team

Conf

Last 10

2004

49

26

Notre Dame

BE

7-3

2003

49

44

BC

BE

7-3

2000

42

32

Villanova

BE

6-4

1999

40

23

Oregon

Pac 10

6-4

It looks like we might as well limit discussions of strong finishes to those occasions when certain State fans begin to dream up new definitions for standard terms.

Stumbling Down The Stretch
While there is considerable reason to doubt that strong finishes impress the Selection Committee, poor finishes are another matter. When looking over the Dance Card analysis and at-large bids from 2001-2005, there are two things worthy of note:

– Only four Bubble teams (ie RPI 36+) with losing records over the last 10 games received an at-large bid to the NCAA tourney.
– Three of the teams “selectedâ€? by the Dance Card formula, but rejected by the Selection Committee, had losing records over the last 10 games.

A losing record over the last 10 games does not necessarily mean that the bubble will burst, but the odds are not good. My conclusion is that it is easier to lose your way into the NIT over the last three weeks of the season than it is to win an at-large bid.

CONFERENCE TOURNAMENT RESULTS

Let’s look at some of the Dance Card misses (predicted in, but fell to NIT) from BCS conferences and NC State’s Bubble Years of 2003 and 2005.

 

 

 

 

Conf

Conf

W/L vs

W/L

Year

RPI

Team

SOS

W/L

Rank

Top 50

Last 10

2005

65*

NC State

42

7-9

1

4-8

6-4

2004

49

Notre Dame

26

9-7

3

4-8

7-3

2003

53

NC State

45

9-7

3

2-8

5-5

2002

43

Villanova

14

7-9

6

3-10

5-5

* New RPI formula

It would be easy to say (and rightly so) that you can’t compare bubble teams from different seasons. However, the BE teams were skipped over for a number of teams with lower RPI rankings…just like State was picked over a good number of teams with higher RPI rankings. What I am looking for is something to explain what the Selection Committee saw that is not included in the Dance Card analysis. I think that it is pretty clear that the columns in the above table do not explain State’s acceptance and the rejection of the BE teams.

The only thing that stands out to me that would elevate State over other teams is the performance in the ACCT. Here are the conference tournament performances for these four cases:

Year

Team

Conference

Tournament Games

2005

NC State

W (135) Florida St.

W (7) Wake Forest

L (4) Duke

2004

Notre Dame

W (97) West Virginia

L (5) Connecticut

2003

NC State

W (76) Georgia Tech

W (7) Wake Forest

L (12) Duke

2002

Villanova

W (66) Syracuse

L (8) Connecticut

There may well be other significant differences that I didn’t find. However, right now it looks like the Selection Committee was really impressed with State’s ACCT wins….and not impressed with close losses to top-10 teams.

THE MORE THINGS CHANGE…
There was an article last spring about the Selection Committee always having one final meeting after Selection Sunday. The purpose of the meeting was to discuss the overall process of selecting and seeding the field of 65. However, the consistency and reliability of the Dance Card suggests that the Committee is not actually changing very much about the Selection Process at all. I’m just not sure if the Selection Committee being so predictable is “good� or “bad�.

FINAL THOUGHTS
Whether you are on the Selection Committee or a message board community, it is a difficult job to sort through the various bubble teams and pick who “deserves� to be in the NCAA tournament. These bubble teams all have some high points to brag about and some warts that they would like to hide. I find it amazing that anyone could go through all of the available data and come up with a system that can sort through the “rough� and come up with some real “diamonds�.

The relative simplicity and outstanding accuracy of the Dance Card’s predictions just amaze me. Their work suggests that a number of major talking points on NC State (and presumably other team’s) message boards have been misguided since the actual data doesn’t support most of the discussion points I have seen in the past.

I suppose it is too much to hope for to expect talking heads and bracket creators to actually attempt to provide some basis for their predictions. My thanks to the Dance Card authors for bucking the trend and providing some meaningful analysis to all of the bubble talk.

About VaWolf82

Engineer living in Central Va. and senior curmudgeon amongst SFN authors One wife, two kids, one dog, four vehicles on insurance, and four phones on cell plan...looking forward to empty nest status. Graduated 1982

General NCS Basketball

7 Responses to The Dance Card

  1. class of '74 01/25/2006 at 6:27 AM #

    Choosing those last 12 teams for the field of 64 is like a referee calling the blocking/charge call. You just have to accept that every year there’s so little difference between #52 and #65 that you could make a case either way. And the PC of automatic qualifiers doesn’t help either thus eliminating a handful of otherwise deserving teams. The only solution for your school is to play well enough to avoid the bubble. It is an imperfect system in an imperfect world.

    By the way was it blocking or was it a charge?

  2. Sammy Kent 01/25/2006 at 1:41 PM #

    Actually, it seems all we have to do to get an NCAA bid is beat Wake Forest in the ACC Tournament. I just checked it out, and going all the way back to the first ACC season (1954), NC State has received an NCAA bid each year we have beaten Wake in the Tournament except one (1999). Here’s the history of NC State vs. Wake Forest in the ACC Tournament:

    1954: Beat Wake in Championship Game.
    1955: Beat Wake in Semifinals. Won Championship.
    1956: Beat Wake in Championship Game.
    1957: Lost to Wake in Quarterfinals. No bid, obviously in those days.
    1960: Lost to Wake in Semifinals. No bid.
    1969: Lost to Wake in Quarterfinals. No bid.
    1983: Beat Wake in Quarterfinals. Won Championship.
    1987: Beat Wake in Semifinals. Won Championship.
    1999: Beat Wake in Quarterfinals. No bid.
    2003: Beat Wake in Semifinals. NCAA bid.
    2005: Beat Wake in Quarterfinals. NCAA bid.

  3. Sammy Kent 01/25/2006 at 1:49 PM #

    ^Actually, I need to make a small correction. In 1955 we did beat Wake, and we did win the ACC Championship, but we were on probation, so we didn’t get the NCAA bid.

  4. Wolfpacklawyer 01/25/2006 at 3:04 PM #

    It’s tough to compare teams from the same year so comparing them from different years is impossible. We of course have to take into account what conference tournament upsets may have closed spots in certain years and the like. All that aside, it appears that State played more teams at the very top or won more games against the very top than the teams compared to, eventhough the records vs. top 50 were similar. I think we can agree that a loss to #1 is not as bad as a loss to #50 and a win against #1 is a better win than a win against #50. State 2005 was 1-7 vs. the top 8 in RPI. Notre Dame 2004 was 1-5 vs. top 8 RPI. Not a big difference, but does help to explain 2 extra losses. State 2003 was 2-4 vs. top 12. Nova 2002 was 0-4 vs. top 11. So two extra quality wins. Your tournament explaination is a good one, but I think that the NCAA also looks at the games against the top of the top, too. It explains some losses that most would have and it provides for some quality wins.

  5. BJD95 01/25/2006 at 3:52 PM #

    It is disheartening to see evidence that non-conference SOS isn’t considered (unlike what our own Lee Fowler said when Georgia got a bid and Alabama didn’t a few years back). That’s an item that teams control, and better OOC games are good for the sport (and thus should be incentivized).

  6. Alpha Wolf 01/25/2006 at 4:34 PM #

    BJD, I agree 100%. To not be penalized for playing East Alcorn Junior College Jayvee Walkon is ridiculous. People WANT to see top teams playing. They only watch the lesser games when a big game isn’t on.

  7. VaWolf82 01/25/2006 at 5:52 PM #

    Your tournament explaination is a good one, but I think that the NCAA also looks at the games against the top of the top, too.

    Well, its obvious that the Selection Committee looks at certain teams differently from year to year. The fact that a bubble team has just beaten a top-10 team in the conference tourney would certainly be fresh on their minds. The key thing is that State cleared the bubble both years and can hopefully move beyond that stage from now on.

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