Evaluating Power 6 Conferences in the NCAA Tournament

UPDATED: to account for 15 ACC basketball teams, not 14
The overall was wrong, I did account for ND, I am just in football mode where we have 14 teams

Taking a look at how the power 6 (ACC, Big East, Big Ten, Big 12, SEC, and Pac 12) perform in the NCAA tournament.

I chose to look at the last 7 tournaments because 1) it's a lot of work to compile, and 2) 2016 was 2 full seasons after the last major change in the conferences, so that's 2 recruiting cycles to compete within your own conference.

For the number of appearances, I stopped at the final four because it's a huge deal to even get to the final four.

The Big Ten gets the most teams in the conference but least in the Elite 8 and Final 4. Now one would expect the ACC, Big Ten, and SEC (which is 4th) to have the most schools in because they are the biggest conferences. If we take the number of schools and multiple by 7 then we get what percentage of the conference made the tournament.

The Big 12 leads the way which makes since because they have the 2nd most Sweet 16, Elite 8, and Final Four teams. The ACC is 4th even though it dominates the upper rounds.

Now looking at the percentage of participants that made it to each round we get the following:

The Big Ten and Big 12 do a great job at winning the first game, but the Big Ten is the worst at going to the Sweet 16. The ACC really shows strength getting to the Sweet 16, as does the Pac 12, who just seems really top heavy from these numbers. They are a major outlier from getting teams to the dance, but the teams they get seem to be good for 2 rounds.

The ACC is trending downwards for invites even though they are the most competitive in the later rounds and just as competitive as the SEC in the first round. The Big Ten is holding steady even though they have had some bad performances. The last Big Ten team to win a national title was in 2002 and from the ACC. Just about every single player in the tournament wasn't alive when the last actual Big Ten team won the title. In the last decade the Big Ten has made the title game three times, both coaches that made it have retired. The SEC has seen one title game in the last decade.

To look at the teams for top end teams (meaning 1 or 2 teams carry the league) we have the chart below show the number of teams from each league that have reached each round:

And then the percentage of conference teams in each round:

The Big 12 and ACC lead the way in getting teams to the Elite 8 and Final Four. The Big Ten has a huge drop off from Round of 32 to Sweet 16. Out of the teams the Big 12 is adding, Cincinnati is really the only one with a chance to make it far in the next few years, but that will change their percentages when adding new teams.

All this has led me to a question, are the teams that make the dance seeded correctly? Does the ACC get bad match ups in the first round so they make the round of 32 at a lower rate than the Big Ten?

I took a different route to see this. I looked at upsets based on seed. To do this, I counted the number of upsets for each of the conferences and then summed the difference in seeding. For example, if a number 1 seed wins it all, they were never upset and they never upset anyone. If a nine seed beats an eight seed, then that is an upset worth 1 point. When UVA lost to UMBC it was an upset worth 15 points. The upsets could happen at any point in the tournament, in the final four and title game, like seeds weren't counted either way.

I counted the upsets both ways, for the conference, and against the conference. Ignored conference vs conference upsets, it's 3 games, happened to the ACC twice, most notably when Cuse beat UVA in 2016.

Looking at the table above, the ACC has cause 21 upsets and been at the losing end of 17 (mostly UVA).

In the 3rd column, per upset, having a higher number means that the conference punched above its weight. As you can see the ACC has the most upsets and beats all but the PAC 12 for the difference of seeds per upset. Now the PAC 12 really had one outlier year, 2021, where UCLA made the final four as an 11 seed AND Oregon St made the Elite 8 as a 12 seed. Those two runs account for 7 upsets and 50 of their seed differences. I am going to assume it is very difficult to judge the top teams over the PAC 12 because it is typically a few teams at the top playing a lot of bad teams. The data shows that seeding for the PAC 12 has been pretty messed up.

In the last column, per upset, it is ideal to have a lower number because that means a loss was to a seed much closer to you. If a one seed loses in the Elite 8 to a five seed then it is a lot more palatable than a one seed losing to an eight seed in the round of 32. That is almost the difference between the ACC (difference of 4.4) and the Big Ten (difference of 7.1). The ACC is the only conference that produces more upsets than it is upset. The Big East is the only other conference close. And the ACC has two of the largest upsets (UMBC over UVA, and Furman over UVA), yet they still do the best.

I would like to take this time to shout out to the Athletic department at Purdue for having incredible blackmail material on the selection committee because they have routinely outperformed UVA as the team least deserving of their seed. They have lost 5v12, 4v13, 3v15, and a 1v16. They have one upset when as a three seed they beat Tennessee as a two seed. Which is one more upset than UVA.

The last part of this I wanted to share was the percentage of upsets based on the number of teams:

The Big East is the only conference that is at the losing end of an upset less than the ACC. Both the ACC and Big East are way ahead of the other conferences in limiting the upsets of their teams. The SEC and PAC 12 are often incorrectly seeded and for the SEC they just don't have the teams to compete at a national level.

The ACC cause more upsets as a percentage of their teams than any other conference and at twice the rate of the Big 12. To the defense of the Big 12, they often have one seeds that dominate the tournament and that is just not shown in these numbers. They are a good conference but often the 2nd tier teams are incorrectly seeded.

The ACC has had one bad tournament, 2021, where they had a terrible first round, and was the only time in the seven years to not make the Elite 8. The SEC has done that three times, including this year.

So now for my soap box (which might not be backed by this data)! If you look at teams winning, the ACC, Big East, and Big 12 are the basketball leagues by far. The Big Ten, SEC, and PAC 12 don't show up when it counts. The ACC is consistently put in lower seeds than they deserve while other conferences often get better seeding and then do nothing with it. The SEC are upset at a high rate, they aren't getting better, they are just getting more teams in the tournament. The merit doesn't seem to be there over the last seven tournaments. It was 2018 the last time the Big Ten didn't get the most teams in the tournament. The Big Ten and the SEC have better media deals which show their games more which help voters and people on selection Sunday make choices that aren't backed by merit.