As March arrives each year, much of the discussion among hardcore NCAA basketball fans revolves around the proverbial NCAA Tournament "bubble." The big question is not who will win their conference tournaments, but which 65 teams will gain a spot in the NCAA Tournament. By the time the conference tournaments end on Selection Sunday, the suspense will be all but over for about 55 to 60 teams. That includes teams that have gained automatic bids by winning their conference tournament (or regular season championship in the case of the Ivy League) or are clear-cut locks based on their won-loss record. That normally leaves about 15 to 20 teams squarely on the infamous bubble. Those schools and their fans will be forced to squirm as the brackets are unveiled and we learn the identity of the fortunate 65.

The process by which the NCAA Men's Basketball Tournament Selection Committee chooses the 34 at-large bids (those teams that did not gain automatic entry by winning their conference championship) is not an exact science, but the major selection criteria are as follows:

• RPI -- The RPI (Rating Percentage Index) is a statistical tool used by the Selection Committee to rank every Division 1 school in America. The index takes into account each team's winning percentage, the winning percentage of its opponents and the winning percentage of its opponents' opponents then applies an inflator/deflator to each game depending on whether it was played at home or on the road. The Committee relies heavily on the RPI which rewards teams that play a difficult schedule and penalizes teams that line up creampuff opponents outside of conference play. To cite an example, the Georgia Bulldogs were 16-14 in 2001, but were invited to the tournament because they played the toughest schedule in America and were ranked 27th in the RPI standings. Between 1995 and 2005, no eligible team with an RPI better than 33 was left out of the tournament. That all changed in 2006 when #21 Missouri State and #30 Hofstra were not invited to the NCAA Tournament. This was not entirely unexpected, however, because the RPI formula was changed three years ago (an incredibly stupid move in my humble opinion). Since 1995, only seven teams with RPIs above 60 have made the tournament as at large selections. Those teams were Stanford (63rd in 2007), Iowa State (62nd in 2005), NC State (63rd in 2005), Wyoming (63rd in 2002), Minnesota (66th in 1995), Air Force (70th in 2004) and New Mexico (74th in 1999). New Mexico's invitation was almost certainly made possible by the fact that their Athletic Director and League Commissioner were on the Selection Committee. The fact that Air Force was invited to the tournament in 2004 with an RPI of 70 shows that the Committee is thinking very differently about the selection process these days. What they were thinking is hard to figure. The following table shows just how important RPI has been over the past decade:




% of Eligible Teams Invited to Tournament
RPI Rank	1995-2005	2006-07
0 to 29	100%	97%
30 to 39	90%	70%
40 to 49	58%	50%
50 to 59	23%	45%
60 to 69	7%	8%
* Excluding Automatic Bids



Note: The RPI formula was changed three seasons ago and most experts agree that the modification has had a negative impact on the RPI ratings. For example, in 2006-07 Southern Illinois (25-7 out of the Missouri Valley Conference) was ranked five spots ahead of Michigan State (22-6 out of the Big Ten). This makes no sense. Based on the brackets of the past three years, it appears that the Committee now relies less on RPI than ever before.


• Conference Winning Percentage/Standings -- In the six major conferences (ACC, Big East, Big Ten, Big XII, SEC, Pac Ten) and even the second-tier conferences (Atlantic 10, Conference USA, Mountain West, WAC), a team's record in conference play is one the most important indicators determining whether or not the team will be invited to the "Big Dance." Rarely will the NCAA Selection Committee invite a team that finishes below .500 in regular season conference play. It is also rare for the Committee to bypass a team in the league standings (or division within a league) to invite another team that finished lower in the standings. Between 1996 and 2004, the only two times that a team in one of the six major conferences was bypassed occurred in 1998 when Florida State (6-10 in ACC play) was invited and 7-9 Wake Forest was not and in 2004 when Texas Tech (9-7 in the B12) was taken ahead of 10-6 Colorado. Since 2005, however, seven teams in major conferences have been bypassed. Florida State is the only team since 1996 to finish four games below .500 in conference play and receive an at-large bid. I doubt that will ever happen again.
  
  Since 1995, 90% of teams that finished above .500 in one of the six top conferences (excluding automatic qualifiers) were invited to the Tournament (287 of 319). Of the 32 that did not, only 13 had an RPI ranking better than 60 (seven of those were Big East teams). By contrast, only 30% of the teams in those six conferences that finished exactly .500 in league play were given a bid. A final note on conference winning percentage: between 1995 and 2006, only six teams from one of the six major conferences finished four games above .500 in conference play and were not invited to the NCAA Tournament (West Virginia, 11-7 in 1997; Nebraska, 10-6 in 1999; Boston College and Seton Hall, 10-6 in 2003; Colorado 10-6 in 2004; Indiana 10-6 in 2005). It happened twice last year (Syracuse and Kansas State, both 10-6).



• Road/Neutral Court Record -- Because no one plays home games in the NCAA Tournament, the Selection Committee looks closely at a team's road and neutral court record as an indicator of how well they will perform in the NCAA Tournament. The Committee will look favorably on teams that have shown the ability to win on the road and may look unfavorably on a team with a poor record away from home.



• Record in the Last 10 Games -- The Selection Committee loves a team that rolls into March Madness on a hot streak. A team in a major conference with 23 wins will certainly not be excluded from the tournament if they finish the season with a 3-7 record in their last ten, but for a team on the bubble, late season performance could mean the difference between a spot in the field of 65 and a trip to the NIT.



• Record Against the RPI Top 50 -- Typically, more than 90% of the RPI Top 50 earns a bid to the NCAA Tournament so a team's record against this group is a good indicator of how they will stack up against the field of 65. The Committee pays very close attention to road wins against teams with strong RPI rankings.



• Total Wins -- It was once believed that a 20-win season in a major conference would guarantee a spot in the NCAA Tourney. This is no longer the case as Colorado found out last year. Twenty wins in a major conference makes a strong statement but it will not, by itself, earn you a "dance card." At one time, teams from small conferences could only gain entry to the NCAA Tournament by winning their conference championship. Now, these so-called mid major programs are competing for at-large bids with middle of the pack teams from the major conferences. In 2006, the Missouri Valley Conference sent three at large teams to the NCAA Tournament, the same number as the ACC, Big 12 and Pac Ten.

Unfortunately, many of the talking heads that we see on television this time of year making predictions about who will and will not make the tournament don't seem to have a firm grasp on the Committee's criteria. If you listen to Dick Vitale, you'd swear that there are 90 teams in the Tournament. If you listen to Jay Bilas, you might think that there are only 50 teams invited and that the Big East is only allowed two. The major sports websites like CBSSportsline and ESPN don't seem to be very accurate either. One very good source for bubble information is Jerry Palm's collegerpi.com. The man knows his March Madness and is more accurate at predicting the field than anyone else I've seen.

In 2003 and 2004, I used statistical modeling to predict the final field of 65 teams. In 2003 and in 2004, my model correctly predicted 32 of 34 at-large teams. The 2003 model predicted that Seton Hall and Boston College would make the tournament and that Indiana and Alabama would not. Despite the results of my model, I fully expected Indiana to be in the field of 65. You could have knocked me over with a feather when I saw the name "Alabama" appear on the brackets. In 2004, my model included LSU and Utah State, two teams that failed to be invited to the NCAA Tournament. The model predicted that Richmond and UTEP would be the last two left out. Both teams were invited to the tourney.

Unfortunately, the NCAA changed a perfectly good RPI formula rendering my models useless. RPI was the major factor in all three of my models. Because the history (the old RPI formula) does not match the current year (the new RPI formula), the predictions and odds do not make any sense. For example, my 2005 preliminary model (thanks to the new RPI) predicted that the MAC would get four bids. It appears that the new RPI formula inflates the rankings of mid-major schools. It's also ruined the rankings within the big conferences. To illustrate, the Pac Ten was the second highest ranked conference according to the RPI in 2004-05. Anyone who follows the sport knew that the Big East, SEC and Big XII were far stronger conferences. The RPI was never perfect, but now it is almost as useless as the BCS.

Please take a look at my 2007 non-statistical Bubble Watch page.

If you like to see the NCAA Tournament Bubble Watch statistical model from 2004, please click HERE.