In the last decade of tournaments, there has been at least one upset from a 13, 14, or 15 seed. Of the 24 such upsets since 2002, half have occurred in the last five years. What is especially remarkable is how consistent several data points are (based on kenpomeroy‘s pre-tournament adjusted efficiency stats) for these March Madness miracles.
All but two 2, 3, and 4 seeds that were upset had less than 14 rank difference between their adjusted offensive and defensive efficiency. Raising that number to a 25 rank difference still leaves us with 17 of 24 (71%) favorites who have a significant difference in how they play depending on whether they have the ball or not.
Similarly, only one underdog in these matchups had less than an 18 rank differential (2014 Mercer) between offense and defense. Only one underdog had a negative adjusted efficiency margin and defensive rank above 145 (2012 Norfolk St. for both). On offense, only three 13 or 14 seed upsets had an adjusted offensive efficiency rank above 135. Only five 13, 14, or 15 seeds had an adjusted efficiency margin of 5.5 or less and a rank worse than 105 . Three of those teams were 15 seeds.
Also, only two teams came from conferences with an overall adjusted efficiency margin worse than negative ten, three teams total worse than negative 8.5, and five total worse than negative 6.
Our parameters for a miracle upset:
- 2, 3, or 4 seed favorite with a 14-25+ rank difference in adjusted offensive efficiency and adjusted defensive efficiency.
- 13, 14, or 15 seed underdog with a 18+ rank difference in adjusted offensive efficiency and adjusted defensive efficiency.
- Positive adjusted efficiency margin overall, better than 5.5, and rank, better than 105.
- Adjusted defensive efficiency should not be beyond rank 145.
- Conference affiliation matters to a minor extent, but should be no worse overall than negative 6.