Bracket Science: Surefire ways to measure a team's NCAA potential

Bracket Science: Surefire ways to measure a team's NCAA potential

Since 1985, the NCAA tournament has been structurally consistent -- with the same number of teams (okay...so the last few years have had a 65th bid), the same seed match-ups, and even the same days that rounds are played. That consistency is a big reason why historical data has such relevance in predicting future outcomes.

It would be a mistake, however, to think that the dynamics of the 1985 tourney are the same as those of last year's dance. The tourney has evolved over the last 24 years, becoming lower scoring, more guard-dominant, and ruled by younger teams, to name just a few volatile characteristics. Here are the top 15 trends altering the mechanics of March Madness.

Trend #1: Conference Composition.

With all the talk of parity in college basketball, you'd think that the numbers would show an increase in the tourney participation of Mid-Major and Small conference schools. In fact, the opposite is true.

Before we analyze the impact of Mid-Majors and Small conferences, we need to clarify where the line gets drawn between the two. My rule for defining a Mid-Major is this: if a conference has had multiple bids in at least one year over the last decade, they're a Mid-Major. Otherwise, they're a Small conference. The last decade has had 11 Mid-Majors: the Atlantic 10, Big West, Colonial, Conference USA, Horizon, Mid-American, Missouri Valley, Mountain West, Sun Belt, West Coast and Western Athletic. But that doesn't mean they've always been Mid-Majors...or that they're the only Mid-Majors since 1985. Who can forget conferences like the Metro and the Great Midwest?

By this definition, the number of Mid-Majors getting tickets to the dance has actually decreased over the 24 years of the 64-team tourney era. Meanwhile the number of Small conferences has increased -- as has the number of Big Six teams. Take a look at these numbers:

If you divide the modern tournament into three eight-year periods, mid-majors have lost an average of five bids to the tourney from the 1985-1992 era to the current 2001-2008 era. Those five lost bids have been scarfed up mainly by the Big Six (an increase of 3.5 bids), but also by Small conferences (a 1.5-bid bump). Part of the increase of Big Six conferences can be attributed to the reclassifying of Conference USA teams like Louisville and Marquette. But there's no denying the numbers: Mid-Majors are not gaining more representation in the tourney; they're losing it.

It would be one thing if these fewer mid-major schools were actually outperforming seed expectations. But they aren't doing that either. In the early era of the modern tourney, mid-majors were slight overperformers, with a performance against seed expectations, or PASE, of +.010. In this most recent eight-year stretch, they're slight underachievers (-.008 PASE). That's at least an improvement over their performance in the middle period of the 24-year modern tourney era, from 1993-2000, when they had a -.058 PASE. Meanwhile, Small conferences have steadily improved over the three eight-year periods. They've always been underachievers, but their -.007 PASE since 2001 is closer to expectations than their -.033 PASE between 1985 and 1992. It's also a tad better than mid-majors. Of course, the Big Six has always been the best performer among conference types. Their most recent PASE is just +.007?down from their strong +.055 showing from 1993-2000. Still, it constitutes overachievement.

The bottom line: mid-majors are getting to the dance less often than in the past...and they continue to underperform. Small conferences are making small improvements in both representation and performance. And the Big Six conferences are dominating the field more than ever before -- while continuing to defy seed expectations.

Trend #2: Coaching Experience

Since 1985, the typical tournament team has been led by a coach with 5.6 years of March Madness experience. That's the overall average. If you looked at the three eight-year periods of the 24-year modern tourney era, you'd find that 1985-1992 fielded the least experienced coaches (5.3 dances under their belts), 1993-2000 featured the most experienced coaches (5.9 dances), and the most recent period falls in between those extremes (5.7 dances).

Oddly enough, the first eight years of the 64-team era saw the fewest number of first-year coaches in the dances. Only 21 percent of the coaches between 1985 and 1992 were tourney rookies. Meanwhile, 1993-2000, the era when coaching experience was at its highest, also saw the highest percentage of coaching newbies (25 percent). These figures were more than offset by the fact that 1993-2000 featured a higher number of veteran coaches with at least ten tourney trips (21 percent to 18 percent for the other two eras.

If you just averaged out the number of trips for non-first year coaches, you'd find that repeat coaches in 1985-1992 averaged 6.5 tourney bids, 1993-2000 coaches averaged 7.5 bids and the most recent era of coaches has averaged 7.0 bids. What I find interesting is that there appears to be an inverse correlation between tourney upsets and coaching experience. In 1985-1992, the era where there were less experienced repeat coaches (6.5 bids) and fewer "deer-in-headlights" rookie coaches (21 percent), upsets were at their highest (10 per tourney). Conversely, in 1993-2000, the period where there were more experienced repeat coaches (7.5 bids) and more rookie coaches (25 percent), upsets were at their mildest (7 per tourney. The most recent eight-year period has been in right in the middle: with repeat coaches averaging 7.0 bids and newbie coaches occupying 22 percent of the bracket slots, upsets have been exactly in the midpoint between seven and ten (8.5). Eerie. Maybe there's something to this correlation -- and maybe it's a coincidence.

One thing is for sure though: coaching experience has never had a stronger connection to overachievement than it has in these last eight years. If you look at the PASE values of coaches making their first trip, between two and five trips, or more than five trips to the dance, rookie coaches have always been underachievers. Since 2001, they're just slight underperformers (-.005 PASE)...but that's the best they've been over the three eight-year periods. On the other hand, coaches with more than five tourney trips have never been bigger overachievers. Their +.042 PASE between 2001 and 2008 marks a big comeback over their underperforming -.017 PASE between 1993 and 2000. What about coaches with two to five years of tourney experience? Lately, they're -.028 underachievers...but during the 1993-2000 era, they were solid +.068 overperformers.

Here's another way of looking at whether coaching experience helps in the tourney. Consider the average number of tourney trips for coaches whose teams: 1) make the tourney, 2) advance to the Sweet Sixteen, 3) reach the Final Four, and 4) win the championship. In all three eight-year periods, teams advancing through the bracket are led by successively more experienced coaches. Here's how the numbers graph out:

Not only are teams that go deeper in the tourney led by more experienced coaches, but the size of the experience gap has grown in each of the eight-year periods. Just compare the line for 2001-2008 with the other two eight-year periods: recent Sweet Sixteen survivors are just a little more experienced than their counterparts (8.3 trips to 8.1 for 1993-2000), while Final Four contenders are even more experienced (10.5 to 9.3). And champions? Over the last eight years, coaches boasting an average 14 tourney trips have cut down the nets. The number was just 11.1 between 1993-2000.

The bottom line: coaching experience has always helped confer a performance advantage in the tourney. And, recently, that advantage has gotten bigger.