27 March 2014

Rating Systems Challenge: FiveThirtyEight Volunteers Best Bracket

This post is part of a series tracking the successes and failures of various NCAA Men's Basketball ranking systems and bracket models throughout the 2014 NCAA Tournament. Click here to check out the full series.

Heading into the second weekend of NCAA Tournament play, the FiveThirtyEight and Vegas brackets sit atop the leaderboard.* Interestingly enough, the spread between the best brackets and the worst is only three correct picks out of forty-eight. Will the spread get bigger as the systems start running into Sweet Sixteen and Elite Eight match-ups that they simply didn't foresee?

*Though the LRMC Bayesian, USA Today Postseason and Sports Reference brackets have logged the same number of points as the two leaders, they have fewer points remaining, and thus poorer prospects going forward. 

FiveThirty Eight and Vegas didn't take the lead due to expert upset picking—it didn't expect any of the possible upsets in the Round of 32. Instead, other brackets misfired on upsets and fell behind. Despite the big upsets in this year's Tourney, chalkiness has served the chalkiest brackets well. Even Pure Chalk is beating 83.4% of all brackets in the ESPN Tournament Challenge. But as the leaderboard indicates, no system has an insurmountable lead. And as the status of their Final Four picks indicates, few systems are out of the running.

The only systems that have lost two Final Four picks are NCAA RPI and the Nolan Power Index. Nine of the systems have yet to lose any of their quarterfinalists. Thirteen of the remaining brackets have at two-thirds or more of their picks remaining in each round, on average.

Picks Remaining

The ESPN National Bracket, currently hanging out in sixth place, is in a very strong position going forward. So are our current leaders, FiveThirtyEight and Vegas. But so is 16th-place Sonny Moore, and 13th-place Lunardi RPI. The fact that there are still so many brackets with most of their picks still alive, and that there is so little spread between the best and worst systems in the leaderboard, strongly suggests that this contest is far from over.

There isn't much to report regarding upsets in this round. Together, the systems pick only 4 Michigan State and 8 Kentucky as potential upsets, and both of those games are on Friday. That said, Sparty vs. 1 Virginia will separate the wheat from the chaff. Six systems—FiveThirtyEight, Vegas, Sports Reference, the ESPN National Bracket and the preseason polls—have Michigan State advancing.

How will today's games affect the rating systems' chances going forward? Check back tomorrow—or follow along on Twitter—to find out.

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