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Is there a science to bracketology?

How to Fill in Your Bracket
A sample bracket
A sample bracket
2008 HowStuffWorks

You can try to be scientific about filling in your bracket, but most experts suggest you use your intuition and hope for a little good luck. All games throughout the tournament are single-elimination format, which means if your team loses, you're out.

Round 1

In this round, the teams are cut from 64 to 32. More people lose in this round than in any other. It's important to remember that the higher-seeded teams may underestimate the other team, and many lower-seeded teams will play as hard as they can to win some respect. There's no doubt that there will be upsets during this round -- you just have to guess who it's going to be. However, a No. 16 seed has never beaten a No. 1, so don't even think about it [source: CBS Sports].

Round 2

The teams are cut in half again, from 32 to 16. As the number of teams gets smaller, it gets trickier to pick the winners. The No. 1 seeds are still unlikely to fall to a No. 8 or No. 9 seed, but it's common for at least one No. 2 seed to be defeated. Half of the No. 3 seeds are typically eliminated in this round.

Ro­und 3­­­­

It's in this round, the Sweet 16, that the ­upsets become few and far between. Most of the teams are higher-seeded teams, and the highest-seeded teams win most of their games. You should move these teams to the next round -- but not all of them. There's a good chance that one No. 1 seed will lose this round.

Round 4

The Elite 8 round has only four games, and they're big games. Each team is vying for a shot at the Final Four. Here's where your gut really needs to kick in. You could probably expect at least one or two No. 1 seeds to make it. Other than that, it's anyone's game.

Round 5

The Final Four is another instinctual round. These four teams are trying to win a spot in the Championship game. The 2011 men's Final Four will be in Houston, Texas, April 2 and 4. The 2011 women's Final Four will rock Indianapolis, Ind.

Round 6

Two teams will have each played (and won) six post-season games and played 30 to 35 regular-season games to make it to this round. The winner will be named the national champion. And either team could win. If you just don't know who to pick, go with the higher seed. But if your gut tells you to pick the lower seed, then do it. If you're still in the pool at this point, you can probably trust your intuition.

In the next section, we'll take a look at some fans who take the mania of bracketology to an entirely new level.