23 March 2015

Rating Systems Challenge: Vegas, ESPN Decision Tree Pace Field

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 2015 NCAA Tournament. Check out the full series.

We're through two rounds of the 2015 NCAA Men's Basketball Tournament, and we have four systems leading the pack. The ESPN Decision Tree (an ESPN Insider tool for picking brackets) Jeff Sagarin's ratings, Sonny Moore's ratings and Pinnacle's Thursday morning Vegas lines top the standings with 480 total points.* Perhaps, however, the bigger story is just how well most of the systems have performed thus far.

*The Vegas bracket remains the official top bracket in the Rating Systems Challenge, since that system has picked more winners through forty-eight games. ESPN Decision Tree occupies the second spot due to its relative surplus of possible points remaining.

Heading into the Sweet Sixteen, eleven systems have outperformed chalk. Those eleven occupy the top decile of brackets on ESPN. Another two systems (the ESPN National Bracket and the USA Today Preseason Poll) have matched Pure Chalk's performance but have more possible points remaining.

The systems are collectively outperforming by another measure, as well: the Rational Pastime pool I set up to track the systems on ESPN is currently the tenth best group out of tens of thousands overall. Heading into the second day of the second round, the pool was ranked fourth.


One of the reasons the pool has performed so well was these systems' success in picking upsets. Collectively, the Rating Systems Challenge brackets identified eight potential upsets on Saturday and Sunday (an upset being any pick that is higher than the original top seed in that segment of the bracket). Four upset picks paid out, four did not, and three evaded their predictions.

Check back on Wednesday or Thursday when I cover the upsets that the brackets are picking for the Sweet Sixteen, and how the outcomes of those games might decide which system is 2015's system to beat all systems.

Follow along between posts: check out the Rational Pastime Tournament Challenge Group.

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