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How To Win That NCAA Pool

Tom Van Riper

How tough is it to win an NCAA tournament pool?

As you fill out your bracket this week, consider that some 40 million fellow Americans will be joining you. That's about one in seven people across the country, only a small fraction of whom could conceivably be hardcore college basketball fans. Bracketology has become to late March what Super Bowl viewing has become to early February--everyone wants to play.

Picking a perfect bracket is nearly impossible. There are over 9 quintillion (that's a nine followed by 18 zeroes) possible combinations to pick over 64 teams, six rounds and 63 games. Even assuming a 90% chance of success in each game, the odds of getting through the tournament with an unblemished sheet are 763 to 1, according to R.J. Bell, president of pregame.com, a Web site that provides insights and trends to sports bettors (the math: 90%, or 0.9, raised to the 63rd power).

If you're playing an online challenge against millions on ESPN or Yahoo! (nasdaq: YHOO - news - people ), good luck. Using favorite colors or cool nicknames to choose winners provides as good a chance as any scientific method. In fact, when the pool is that big, the best chance of winning is to throw the rules of probability out the window and just hope your crazy picks pan out.

But an office pool with 50 or so co-workers is a different story. Paying attention to historical trends can give you a leg up.

"The beauty is that it's a repetitive event," Bell notes of a tournament that has held to the same 64-team formula for 23 years. "The variables don't change, no matter what the teams are."

The biggest mistake people make? Falling too hard for a favorite dark horse. Upsets are common, but those teams seeded lower than 12th (there are 16 teams in each of the four regions) that pull a first round upset virtually never advance any further.

"Some people get emotional and have these teams going to the final four, and it's just not going to happen," says Bell, who holds a finance degree from Ohio State University. So go ahead and pick 14th seeded Boise State to knock off Louisville in the first round of the East regional, but don't expect them to keep marching onward.

Even in the first round, teams seeded 13th through 16th have combined to win just 18% of the time since 1985, the year the tournament expanded to 64 teams. First-round upset picks are best confined to the nine-through-12 seeds; in fact No.12 seeds have beaten No. 5 seeds 11 of 28 times over the past seven years. Historically, No. 10 and No. 12 seeds that pull first-round upsets also win in the second round nearly half the time.

Another common mistake: picking top-seeded teams to fold too early. Not only has a No. 1 seed never lost an opening-round game, but 87% of them have won the first two rounds over the last 23 years. So pencil North Carolina, Memphis, UCLA and Kansas into at least the third round. And if trends hold, three of them will reach the Elite Eight and one or two of them will play in the Final Four (19 of the past 23 years have seen exactly one or two No.1 seeds reach the final weekend). In the meantime, bid farewell to your dark horse team after the second round--of the 20 teams seeded 12th or lower that have reached the final 16, only one has ever taken the next step to the Elite Eight.

As your bracket fills out, don't pick any team seeded lower than No. 8 to advance to the Final Four--only two such teams have ever made it. And the cutoff for reaching the title game is a No. 6 seed. No team seeded lower has made it to the final Monday night since eighth-seeded Villanova in 1985.

Perhaps Brigham Young or Mississippi State, each a No. 8 seed in 2008, will be this year's Villanova. Just don't bet on it, unless you're playing online.