How are the college football rankings determined?

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BCS stands for Bowl Championship Series. It turns out to be one of the most complex statistical systems that we can encounter in daily life. Unlike other National Collegiate Athletic Association (NCAA) sports, college football does not have an end-of-season tournament or playoff series. Instead, any Division I-A team with a winning record can play in a post-season competition called a bowl game. These games bring publicity and money to the colleges and universities that participate in them. But with winners of 25 different bowls all claiming to be the number one, it’s been hard to call any one team the “National Champion.” In 1998, the Bowl Championship Series debuted and promised to solve this problem. The BCS divides the glut of post-season games into two groups:

Teams compete throughout the year to participate in one of the four high-profile BCS games. To figure out who gets to play, a complex, mathematical formula is used to rank the top 25 teams throughout the season. Each Monday, the BCS ratings are updated based on the teams’ performances during the previous week. At the end of the regular season, the top two teams in the ratings play each other for the national championship. The calculations performed by a small number of mathematicians and statisticians off the field are more important to a team’s chances of being in the final game than their efforts on the field. No college football fan can deny how important mathematics is to everyday life after seeing this formula.
The competitors for the other three bowl games are chosen from teams who end up in the top 12 of the final ranking. These bowls don’t pair off No. 3 vs. No. 4, No. 5 vs. No. 6, and No. 7 vs No. 8, because bowl organizers also factor in regional considerations, like what conference a team comes from. They want to pick a team that will attract a lot of fans and advertising dollars to their game. Once again, math plays a role in these financial forecasts.