The 12-Seed Anomaly
March 18, 2008
There are two things that every good NCAA tournament bracket-filler-outer should do immediately upon receiving their tournament layout hot off of the company copy machine each year. First, put the name of the No. 1 seeds in each region on the next line. Second, put the name of the No. 2 seeds in each region on the next line. No matter how much you like some low-level school’s mascot or team colors, it’s just not worth trying. No. 1 seeds are 100-0 all time against No. 16 seeds since the tournament increased to 64 (now 65) teams. As for No. 2 seeds, only four times in 100 games have they lost to an opponent seeded 15th – so write those in ink as well.
This brings us to step number three: the 12-versus-5 matchup. This, my friends, is where the magic happens. The spirit of the tournament lies in the upsets, the little schools outplaying the big ones, the Cinderella squads finding out that the slipper actually does fit. This pairing is always the next to consider because of its unique history.
The 12-versus-5 matchup doesn’t follow mathematical logic. Assuming all else is equal, the tournament selection committee should be able to rank and seed teams over the long run to fall in line with statistical probability. For example: a number one seed should never lose to a number 16 seed. To this point, the No. 1 seeds have won 100 percent of those games. The game between the eight and nine seeds, conversely, should for all intents and purposes be 50/50. In the history of the tournament, the record between the two sides is 54-46, in favor of the nines.
So, the winning percentage of the underdog teams (16 through nine seeds) should progress somewhat evenly from zero to 50 percent. If I’ve already lost you, it might be time to quit while you’re behind. In fact, we’d recommend calling a few of your former math teachers and clarifying how much your parents actually spent to get you through school.
The winning percentage of No. 15 seeds versus No. 2 seeds, as illustrated earlier, is 4 percent. Moving up to the 14s, they are 15-85 all time against third-seeded teams, giving them a winning percentage of 15. The 13 seeds keep the trend going, winning 21 percent of the time (21-79 overall).
Let’s skip No. 12 for now and go to 11. Against No. 6 seeds, the 11s have a winning percentage of 31 from a 31-69 overall record. And finally, the 10s beat the 7s 39 percent of the time (39-61 overall).
So, judging by those numbers the No. 12 seed should have a winning percentage around 25 percent, right? Well, the math makes sense, but reality doesn’t. With a 34-66 record all time against No. 5 seeds, the 12 seed wins 34 percent of the time – better than the No. No. 11 seeds by 3 percent.
The overall numbers have skewed in this direction in large part because of recent history – with the exception of three years ago when the No. 5 seeds went 4-0 while the No. 6 seeds split games with the 11s.
Since 1999, 12 seeds have done a better job in the first round of the tourney than 11 seeds. In the last 11 years, 12 seeds have gone 18-30 against their No. 5 counterparts, while No. 11 seeds are just 13-35 overall against the 6s. This averages to 1.6 first round victories per tournament for the 12s and 1.2 for the 11s.
Now that I’ve beaten the living daylights out of you with statistics, let’s talk strategy. Every so often its fun to throw a 13 or a 14 seed on the line to advance to the next round and see what happens. This is fine, just realize that both of those seeds average less than one victory per tournament over the last 23 years. But when it comes to those 12s, you’ve actually got to take a serious look at all four games. First, look at the trends. Find out what teams are hot heading into the tournament and what teams have struggled as of late.
The next piece of the puzzle to look at is strength of schedule – particularly late in the year. If a team has a mediocre record down the stretch, but is playing top competition, that doesn’t necessarily mean they are playing poorly. That’s where a few box scores come in handy. And just because a team is on a winning streak doesn’t mean they’ve beaten anyone of note (exhibit A this season is Butler).
Another key factor is matchups. Does one team have two quick guards that no one on the other team will be able to defend? Perhaps an opposing big man will cause some problems. Again, this is where you dig up the season schedules and look for teams similar in makeup to the upcoming opponent and see how the games went. To be quite honest, this is the way to look at any matchup. But when it comes to picking the one or two key upsets – in particular at the 12-versus-5 level – generally you can look back and find the glaring statistic after the fact that should’ve pointed you in the right direction. Finding the stats in advance is the hard part.
But don’t quit until you find at least one 12 seed you’ll put your money on the line for. The 2007 tournament marked just the second time since 1989 that at least one 12-seed did not move on to the second round. Six times in the last nine years, two or more 12 seeds have moved on to round two.
Keep in mind, however, the magic generally ends there. Of the 56 No. 12 seeds to play in the tournament since 1995, only eight have advanced past the second round into the sweet 16. Just one of those eight teams has made the elite eight. In all, 16 No. 12 seeds have made the Sweet 16 in the 25 years of a 64-team bracket (or 65), making for roughly one No. 12 in the final 16 every two years. But as stated, more recent history dictates even fewer appearances, as eight of those 15 No. 12 seeds made the Sweet 16 from 1985 through 1994 – leaving eight for the last 15 years.
Three No. 12 seeds advancing in 2009 skewed the numbers even more in the direction of the No. 12 seeds as statistical anomalies. And keep in mind, 25 tournaments isn’t a gigantic sample size. In the next 50 years, the numbers are likely to fall along a normal curve – meaning 12 seeds would have to start losing at a higher rate. But as the numbers above indicated, the 12 seeds have been the exception to the rule the last 20 years, so until they prove otherwise, there is something special about the 12 vs. 5 matchup. Be sure to take note before turning in your bracket.
Want even more seed history stats? Check out my other tourney post: http://puntingbaxter.wordpress.com/2010/03/16/more-bracket-busting-fun/