- Matt Cox
I should probably start off by declaring that the title of this article is, to some degree, 'clickbait', given that in my heart of hearts I'm still not sold that the 2016-17 Big 12 conference is, definitively, the best of all time (gotcha!) - according to both myself and my colleague Ky, this trophy probably belongs to the 2003-04 ACC, which featured a murderer's row of 9 sluggers, including two Final Four squads (Duke & Georgia Tech), a Wake Forest team that had a guy by the name of Chris Paul at point guard and a North Carolina team with essentially the exact same roster as the following year's team, who would go on to win the national title after taking down an all-time great Illini squad (Dee Brown, Luther Head, Deron Williams, etc.) in St. Louis. And even with the embarrassment of [talent] riches up and down the Deacons and Tar Heels rosters, getting to .500 in league play was still a struggle that season (Wake finished 9-7 & UNC finished 8-8 in the ACC).
HOWEVER, as I recently embarked on an exploration through countless college basketball specific advanced analytic sites, I discovered that there is a real argument to be made that not only is this year's Big 12 conference historically great, but the league's recent multi-year dominance, specifically over the past 3-4 seasons, is simply unprecedented in the last 15 years of college basketball.
Over the weekend, I wanted to write about the best mid-majors in college basketball right now (stay tuned), but hit a major roadblock before I even began - How do we technically define what conferences qualify as "mid-majors"? I was initially trying to sort all 32 leagues by their average year-over-year ranking, as defined by some reliable statistical metric, to see if there was some natural drop off between the classic Power-6 conferences and the rest of the field, or the Power-6 + A-10 + AAC + Mountain West + MVC and the rest of the field. You may not be surprised to find that I settled on kenpom.com's Adjusted Efficiency Margin statistic (AdjEM) for my go-to data-driven metric which, at its core, assesses how good each conference is on a schedule-adjusted and points per possession basis, relative to that specific year's college hoop landscape.
As I began to gather and analyze this data for the past 5+ years, I couldn't help but notice how consistently high the Big 12 scored, especially compared to the other traditional powers (ACC, Big East, Big 10, etc.) over the past three seasons. Before diving into to why the Big 12 has been so dominant per the advanced numbers, we must understand on how kenpom.com - the basis for this analysis - ranks the top-to-bottom quality of each conference. That italicized portion of the last sentence is critical because it's where many of you reading this might deviate in your own perception on which leagues are better than others. Kenpom's AdjEM method values the entirety of the league (i.e. "top-to-bottom") and some may argue this approach de-values the potency of elite teams in certain conferences, such as the Big East in 2010-11, which sent a NCAA record 11 teams to the Big Dance, but wasn't even the highest ranked conference in that year (see chart below)! The bottom-line is that using the AdjEM metric as the standard to compare conferences in any given year is certainly open to debate and I fully respect the opposing argument that places a premium on the number of higher quality teams at the top of the standings.
With that disclaimer established, I'll now provide a real life example of how to comprehend the AdjEM number when evaluating the overall quality of each conference on yearly basis - this should help make the statistical nuances of the rating system easier to digest:
The numerical rating of each conference is expressed as the numerical rating of an individual team that would be projected to go .500 in that conference over the course of the year. So let's make this description real with an example from this season: The Big 12 conference currently has an AdjEM rating of 19.37 - If you sort all 351 teams in kenpom by their overall AdjEM, you'll find that 26th ranked Notre Dame (20.47) and 27th ranked Michigan (18.43) have the closest AdjEM ratings to a 19.36. This implies that if you put Notre Dame OR Michigan in the Big 12 this season (which would then give the conference 11 teams), the advanced statistics - at least the formula used by Ken Pomeroy - would predict both the Irish and the Wolverines to finish around 10-10, or .500 in league play (assuming a true round robin, which all conferences should have). Just for context, Notre Dame is currently 10-5 in the ACC (4th place out of 15 teams), while Michigan is 7-7 in the Big 10 (7th place out of 14 teams). Quick tangent: Michigan is an intriguing case study because even though they currently hold a pedestrian .500 record in what is considered to be a down Big 10 conference (a notion I agree with), if you put Notre Dame and the Wolverines on a neutral floor tonight, the oddsmakers in Las Vegas would likely set the line within 1-2 points of a pick 'em - in other words, both teams are regarded by the smartest guys in the room to be of equal caliber.
So with that explanation, hopefully the chart below is easier to interpret. Over the past 7 season, there have been a total of 8 conferences with an AdjEM above 16 (see highlighted cells) - the Big 12 holds claim to three of them...
In fact, since 2010-11, no other league posted an AdjEM above 18 - the Big 12 is currently reppin' a cool 19.36!
The upper-echelon of the 'Big Bad 12' features 2-3 legit Final 4 contenders in Kansas, Baylor and West Virginia. If the season ended today, according to bracketmatrix.com, Kansas would secure a 1-seed and Baylor would be the on the fringe between a 1-seed and a 2-seed. These two Big-12 bosses are currently ranked 3rd & 5th respectively in the overall S-curve - compare that to the ACC, whose top-2 teams (UNC and Louisville) are slotted at 4th & 6th respectively. Not yet mentioned is 'Press Virginia', who actually supercedes both Kansas and Baylor in kenpom's overall AdjEM rankings at 3rd overall, which is higher than any other Big 12 or ACC team, including Duke and Virginia...
The key point to make for the Big-12 as the best league in America this season is that no other conference can match the quality of their top-tier and the competence of their bottom-tier. The ACC certainly makes a strong case at the top, especially when you throw in the likes of North Carolina, Louisville, Duke and Virginia to the conversation - but here's the thing - the key assumption in my argument that the Big-12 has a comparable "top-tier" to the ACC all comes down to how you define "top-tier". My personal bias, which is to some degree already reflected in Ken Pomeroy's AdjEM calculation mechanics, is that "top-tier" should be based off the top X% of teams in the league and not necessarily a set number, such as top-3 or top-5, especially when comparing conferences that don't have the same number of schools.
For example - if we choose to define the "top-tier" of both leagues as the top-20%, that would equate to the top-2 Big-12 teams (20% of 10 schools) and the top-3 ACC teams (20% of 15 schools). Thus, in order to debate who has the best "top-tier", you have to first agree on who are the two best teams in the Big-12 and the three best teams in the ACC and THEN you can debate those two groups of teams head-to-head. While comparing a group of 2 teams to a group of 3 teams doesn't exactly sit well in our stomachs, in my opinion, this combats what I'm calling the "big league bias".
The "big league bias" is rooted in a pretty simple concept: over the long run, conferences with more schools have a higher likelihood of producing a better batch of top-3 or top-5 teams than a conference with a lower number of schools. In the ACC vs. Big-12 debate, those who fall prey to this fallacy will only focus on discussing who has the better top-3 or top-5 teams, which is unfair given that the ACC simply has more teams to choose from. This is why I feel it's critical to compare percentiles of conferences, such as the top-20% aforementioned example, to not skew the debate in favor of larger leagues. The same theory also applies at the other end of the spectrum - conferences with more schools have a higher likelihood of producing a worse batch of bottom-3 or bottom-5 teams. In this case, the bottom-3 or bottom-5 teams in the Big-12 is significantly better than the bottom-3 or bottom-5 in the ACC. Per kenpom.com, the ACC has three teams - Georgia Tech, NC State & Boston College - all ranked lower than the worst team in the Big-12 (Oklahoma). However, similar to the "big league bias" concept, this argument will tend to favor smaller conferences over larger conferences in the long run.
The overarching point I'm trying to make is that because of the imbalance in the number of teams per conference, in any given year, we must assess the entirety of each conference to get a holistic understanding on who truly is the best - again, that is if you believe the proper definition of the "best league" is the one with the highest quality of teams from top-to-bottom. So while the "top-tier" of the Big 12 and ACC are relatively close, depending on how you think the Big-12's top-20% (pick 2 from Kansas, Baylor & West Virginia) stack up with the ACC's top-20% (pick 3 from North Carolina, Louisville, Duke, Virginia & Florida St.), it's the middle-tier and especially bottom-tier that makes this year's Big 12 historically strong.