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Playing The Numbers Game

How might the RPI affect this year's UCLA team? (Photo Credit: Art)
How might the RPI affect this year's UCLA team? (Photo Credit: Art)

Baseball fans are used to dealing with numbers, especially in modern times. While batting average, home runs, RBI, ERA, wins, etc. have long been a part of baseball, we're now hit with these new numbers like OPS, OPS+, EQA and VORP. Needless to say, baseball fans are pretty comfortable with numbers. When it comes to college baseball, there's a whole other number that plays a huge role in the game and it's one that college basketball fans are familiar with- RPI.

Yes, the Ratings Percentage Index that you hear bracketologists and the selection committee rambling on about in college basketball has a place in college baseball, only it is far worse. When the NCAA decided to take that RPI from basketball and use it for baseball, they made wholesale changes to it, if by wholesale changes I mean absolutely none. The RPI is a basketball formula thrown into baseball without any regard for the differences in sports, specifically the scheduling difference in the sports and it is the West Coast teams who suffer.

To keep things simple, the RPI is 25% your winning percentage, 50% your opponents' winning percentage and 25% your opponents' oponnents winning percentage. As you can see, winning percentage is heavily involved. Now, what happens when two teams play each other? One wins and one loses so the winning percentage for those two teams comes in at .500. That's just the way it works so when you take a look at the West Coast and Southern California specifically, where teams all play each other a lot, those winning percentages come back towards .500 the more the teams play regardless of how good those opponents are.

Midweek games are almost exclusively played between teams close to each other so this season, UCLA is playing Long Beach St., UC Riverside, UC Santa Barbara, Cal St. Fullerton, UC Irvine and Pepperdine. Those teams will also play each other pretty often and many of the other Pac-10 teams will also play those opponents. The more all of these teams play each other, the more their winnings percentages come back to .500, which hurts all of these teams in the RPI. That probably wasn't the best explanation of why the West Coast has trouble with the RPI so you might want to take a second and reread that before hopping along with me to find out how this whole RPI things affects UCLA.

Okay, now that we've somewhat figured out the RPI, we need to make note of the fact that even the best of formulas aren't going to give us an accurate idea of which teams are better than which. Numbers can only take you so far, but the RPI is worse than most because it wasn't created for baseball. While UCLA is playing some damn good local teams, their RPI is going down. This isn't a problem in basketball because there's a lot more travel and games against non-local teams, something that wasn't taken into account when dropping the RPI into baseball.

There are other formulas created specifically for baseball, including the Iterative Strength Ratings (ISR), which was created by the man at, arguably the sports' best numbers man. Those do a much better job of accurately rankigns teams, but those have no acutal meaning. Better or not, the ISR and other formulas put together specifically for baseball aren't taken into account when the selection committee meets at the end of May. The RPI is and it's counted upon heavily.

Not only is each team's RPI rank taken heavily into account, but when assessing good wins (over the top 50) and bad losses (versus teams 150+), it is the RPI that determines whether the opponent is "good" or "bad." If you think the basketball selection committee leans too heavily upon the RPI, then you should see how heavily the baseballl selection committee leans upon it. With things the way they are, college baseball very much becomes a numbers game. Coaches put together schedules with one eye on how it will affect their RPI and the other on how it will affect their RPI.

So how is UCLA faring? Amazingly. They are fourth at the moment and while it is still a little too early to live by the RPI you see now (they get to a "true" point sometime around the end of month) they're almost at an accurate point now.

As only the RPI would have it, UCLA is faring better this year than they have in past years despite a weaker schedule. The RPI barely takes into account road games versus home games so UCLA's home-heavy schedule hasn't hurt them and while Oral Roberts, Mississippi St., and Nebraska are all having down years, their variety in region and the teams they play has helped the Bruins' RPI some. Whiel the Bruins' see their RPI dip because of all their common opponents, their non-conference weekend opponents don't play nearly as many common opponents this season.

The Bruins are also looking set to get a nice boost from the Pac-10 this season. While the inherent unfairness of the RPI will not fully reward Pac-10 teams for their successes, the conference is having a banner season so when the Bruins play more Pac-10 teams, they should see a nice boost in their RPI compared to smaller conference teams, even if it won't match the RPI boosts the SEC and ACC are getting.

Not only is Boyd a genius who has put together his ISR and an RPI formula that mimics the one used by the NCAA, but he has also put together what he calls his "RPI Needs Report." Updated daily, just as his ISR and RPI are, Boyd's RPI Needs Report tells you what record each team needs in their remaining games to finish top eight in the RPI, top 16, top 32 or top 45. This formula is dependent on teams continuing to play at a similar level to the one they have to this point in the season and obviously, that won't happen. As a result, the report is not 100% accurate, but it gives you a decent picture at the road ahead.

Right now, Boyd has UCLA needing a 19-12 finish to have a top eight RPI rank at the end of the regular season. A 14-17 finish will net the Bruins' a top 16 RPI finish and a 9-22 finish still keeps the Bruins in the top 32. Now, if a West Coast team can finish with a RPI in the top eight, they're just about guaranteed a national seed. That would mean that if UCLA finished in the top eight in the RPI, they would be a Regional host (assuming they bid and are deemed an acceptable host), a Super Regional host (again, assuming they bid, are deemed and acceptable host and win their Regional) and they would be guaranteed to not play another national seed until the College World Series. A finish outside the top eight in the RPI could still net the Bruins a national seed and anything in the top 20 should get them at least a #1 Regional seed and right to host.

Now, while the RPI is heavily leaned upon and does not favor the West Coast in any form or fashion, it is easy to overstate the hill West Coast teams have to climb in the RPI. It probably came across as an insurmountable hill in this explanation, but be assured, it is not. It is another obstacle, but it can very much be overcome and right now, UCLA is overcoming it and then some. It is important to understand the workings of the formula and how it is used if you want a good idea of how things may play out on Selection Monday though. You could also forget 90% of what is written here and just live by Boyd. Check the RPI, check his Needs Report and live by it. You'll be in pretty good shape with Boyd alone.