Decoding College Football Rankings: A Comprehensive Guide

How do you determine the best team in college football? College football rankings can help you answer these questions, but only if you find the right ones. This article looks at the rankings you should take seriously in making predictions on college football games, whether you’re in a weekly pool, bet on games or just need to feel smart in front of your friends.

The Evolution of College Football Ranking Systems

In the world of college football, ranking systems are the compass by which fans, teams, and players navigate the landscape of the sport. These rankings aren’t just about bragging rights; they have a profound impact on everything from postseason play to recruiting.

In the late 19th century, football was primarily an intercollegiate endeavor, and games were often informal affairs. The birth of rankings can be traced back to 1936 when the Associated Press (AP) initiated its college football poll. The goal was simple: assess the nation’s best college football team at the end of each season. In 1950, the American Football Coaches Association (AFCA) introduced the Coaches’ Poll. Coaches from major college football programs ranked the top 20 teams.

During the 1990s, college football saw the emergence of systems like the Bowl Coalition (1992) and later the Bowl Alliance (1995). These systems aimed to match the top two ranked teams in a designated bowl game, often leading to split national championships. The Bowl Championship Series (BCS) was introduced in 1998 in an attempt to provide a more structured way of determining a national champion. The BCS used a combination of polls, computer rankings, and strength of schedule to rank teams.

The College Football Playoff (CFP) marked a significant shift in college football rankings. In 2014, a selection committee was formed to choose the top four teams to compete in a playoff format, ultimately leading to the crowning of a national champion.

Over the years, college football rankings have evolved and adapted to the sport’s changing landscape. The introduction of the Playoff Selection Committee marked a significant shift. College football rankings are more than just lists of teams; they’re the lifeblood of the sport. Understanding the historical context and nuances of these rankings can deepen your appreciation for the complexity and excitement of college football.

Impact of Rankings

College football rankings are far from mere numbers on a page.

Postseason Play: The most obvious impact is on postseason play. Rankings determine which teams secure coveted spots in prestigious bowl games and the highly sought-after College Football Playoff (CFP).
Recruiting: Rankings are a powerful recruiting tool. High school athletes aspire to play for top-ranked programs.
Fan Engagement: Rankings generate buzz and fuel debates among fans.
Media Exposure: Media coverage often focuses on ranked teams.

Key Ranking Systems Explained

Preseason AP and Coaches Poll

The preseason polls might seem worthless for making predictions. The humans of AP and Coaches have no games upon which to base their ballots. However, this is a mistake. The preseason AP and Coaches poll have remarkable predictive power, even during Bowl season. To show this, we ask how often the higher ranked team in the poll beat a lower ranked team in a bowl game.

Over the past 10 years, a sample of 339 bowl games, the preseason Coaches poll predicted 59.9% of bowl game winners (163-109 with no prediction in 67 games with two unranked teams). To put this in perspective, the team favored by the closing line in the gambling markets won 61.5% of games according to The Prediction Tracker (208-130 with no prediction in one game).

The remarkable predictive power of preseason human polls most likely comes from the wisdom of crowds. No one sports writer or coach can create a perfect ranking. Don’t forget about preseason expectations.

Read also: Crafting Your NCAA Profile

Coaches’ Poll: The Coaches’ Poll, initiated in 1950 by the American Football Coaches Association (AFCA), was an integral part of the Bowl Championship Series (BCS). This ranking system involves head coaches from NCAA Division I football programs.
AP Rankings: The Associated Press (AP) Rankings, introduced in 1936, are decided by a panel of media members. This group of sportswriters and broadcasters vote for their top 25 teams each week during the college football season.

College Football Playoff Rankings

The newest and most influential ranking system is the College Football Playoff Rankings. Established in 2014, this system determines which four teams earn a spot in the College Football Playoff.

College Football Playoff rankings. This committee of 13 people with backgrounds in college athletics has clear importance. With only a few years of data, it’s not possible to say anything of significance about how often a higher ranked team wins a playoff or bowl game. The NCAA men’s basketball tournament has used a selection committee similar to the College Football Playoff committee to select the field and assign a seed to each team.

Let’s stop to appreciate this predictive accuracy. The selection committee consists of athletic directors and conference commissioners. There’s no requirement for coaching experience or a background in analytics. Will the College Football Playoff committee do this well with their rankings? Some factors point in their favor. This committee meets every week starting in late October until the season ends in early December.

However, there are other factors working against the playoff committee. College football provides only 12 or 13 games each season to evaluate a team. As an example, consider Florida State in 2014. The Seminoles won the BCS title the previous year and returned Heisman winning QB Jameis Winston. However, the defense declined in 2014, and Florida State no longer dominated opponents. They had close calls against Notre Dame, Miami and Georgia Tech. Florida State went 13-0 and won their conference championship. The committee ranked them third behind two one loss teams (Alabama, Oregon).

Computer Rankings

There are so many college football computer rankings. Ken Massey compiles over a hundred of them on his site. Modern college football rankings go beyond the final score and use the play by play data from each game.

Sagarin Ratings:
ESPN Football Power Index (FPI): ESPN’s analytics group has developed college football rankings based the idea of expected points added (EPA), or the notion that each play of a game has a point value. To understand EPA, suppose a team has a 1st and 10 at their own 20 yard line. They could drive the length of the field for a touchdown for +7 points or kick a field goal for +3 points. In the worst case, an interception gets returned for a touchdown, netting -7 points for the offense. Given a down, distance and field position, the offense’s expected points is an average of the net points of the next score. Expected points added (EPA) is the points gained or lost from a play. For example, suppose the offense gains 20 yards from that 1st and 10 from their own 20 yard line. Burke calculates 1.3 expected points for a 1st and 10 from their own 40. ESPN uses EPA in college football for their FPI rankings, numbers meant to make predictions looking forward.
Massey-Peabody: To see the top 35 college football teams in Massey-Peabody, click here.
S&P+: Bill Connelly, SB Nation’s college football analytics guru, writes a preview for each and every FBS team, even New Mexico State. These treasures have become the only team previews I read each season. His methods takes each of these factors and adjusts for strength of schedule. These four factors are combined to make the final rankings. Before the 2015 season, Connelly’s rankings depended on only success rate and points per play, which gives the term S&P. We use only four statistics - one each for rushing, passing, scoring and play success. Most likely, they use yards per play for the rushing and passing numbers. The scoring component is similar to the points based rankings mentioned earlier. Combining these metrics lead to powerful rankings.
Fremeau Efficiency Index (FEI): Brian Fremeau uses points per possession to evaluate teams in football. Accounting for starting field position is important. For example, if the offense gets the ball only a yard from the end zone, they should not get full credit for scoring the touchdown. Fremeau publishes his drive based numbers both on his own site and Football Outsiders. The latter site also combines FEI with S&P+ to obtain the F/+ rankings, an aggregate picture of team, offense and defense in college football.

The Power Rank

The Power Rank. A method I developed based on research in statistical physics.

Factors Considered in Rankings

The college football playoff committee has made strength of schedule a buzzword. How does one evaluate a team in the context of which teams they have played? Margin of victory doesn’t get discussed as much as strength of schedule. This lack of attention may have resulted from the old Bowl Championship Series.

To test this with data, we can construct rankings that consider neither, one or two of these factors.

Win percentage: Fraction of games won. Win percentage is hardly better than flipping a coin for each bowl game.
Colley Matrix: The Colley Matrix does better than win percentage but not nearly as good as raw margin of victory.
Raw margin of victory:
Simple Rating System:

Strength of Schedule

Va. Though this may be the weakest part of the equation, it can still make a difference. Last year, pollsters eventually overlooked Wisconsin's loss to Cincinnati, but the computers didn't. The result: the Badgers had an average computer rating of 7.71 despite ranking fourth in both polls.

Va. Strength of schedule carries more weight than just being a category of the formula; it is also factored into most of the computer ratings in some form. Within the schedule strength component itself, teams are ranked 1 through 115 based on the winning percentages of their opponents and their opponents' opponents. Each ranking is multiplied by .04 to give the teams a point value for schedule strength. A difference of 25 spots between teams in schedule ranking amounts to one point -- the same as a one spot advantage in the polls. Schedule strength is most affected by the non-conference games. The key is finding opponents that won't beat you but will beat almost everyone else they play. Last year, Alabama had the top-ranked schedule thanks to a non-conference slate of Southern Miss (8-3), Louisiana Tech (8-3) and Houston (7-4). Too bad the Tide lost to Louisiana Tech.

Bowl Championship Series (BCS) Formula

Understanding the Bowl Championship Series (BCS) formula is easier than it seems. The BCS consists of two human elements, or polls, from which two-thirds of the BCS formula is taken. The human element is used is as follows: First, take the Harris Interactive, which includes 105 voters. If all 105 voters decided to vote one team first, the team would be awarded 105 times 25 points, or 2875 Harris Poll Points. Therefore, a perfect score in the eyes of the Harris Poll voters is a 2625. For example, Ohio State, the BCS’s No. 2 in the seventh BCS standings of 2013, received 2488 points from the Harris Poll voters on November 20, the seventh Harris Poll of the year.

The same calculation is mirrored with the ESPN/USA Today Coach’s Poll. The Coach’s Poll consists of 62 voters, and the scale scoring for votes mirrors that of the Harris Poll’s. For example, Ohio State received 1462 points from the Coaches’ Poll during the seventh BCS week of 2013.

The third and final part of the BCS calculations is derived from six computer rankings posted weekly. The BCS takes the six point values and removes the lowest and highest point values given to a specific team. The BCS completes the procedure by averaging the three values it received from the Harris Interactive College Football Poll, the USA Today Poll and the Computer Polls. That’s it!

Additional Factors in Computer Rankings

Offense Rating: play that leads to scoring will be reflected in the Offense rating. An average defense will be rated at zero.
Defense Rating: step, and as such has no bearing on the overall rating.
Game conditions: they have to. conditions.
Margin of Victory: between a 10-0 win and a 50-40 win. more variance, and less likely to be dominated by either team. scoring game may indicate a defensive struggle, or poor game conditions. which case, a small deficit is more difficult to overcome. in isolation. winning again. is assumed to be normally distributed about a certain mean (its rating). of teams A and B respectively. scored by teams A and B in a particular game. Here ^ denotes an exponent. the ratings and home advantages. optimization function. and they are negligable by the end of the year.

Losses

Va. Each loss obviously hurts a team in both the polls and computer ratings, but just for good measure, the BCS formula adds another point to the team total. This makes it even more difficult for a one-loss team to finish ahead of a major-conference undefeated team. Though Virginia Tech managed to hold off Nebraska in the BCS rankings last year, the Hokies might not have been as fortunate with Tennessee if the Vols hadn't lost a second game at Arkansas.

The NCAA Evaluation Tool (NET)

The 2024-25 men's basketball season marks the seventh season of the NCAA Evaluation Tool (NET) rankings, which replaced the RPI prior to the 2018-19 season as the primary sorting tool for evaluating teams.

The remaining factors include the Team Value Index (TVI), which is a result-based feature that rewards teams for beating quality opponents, particularly away from home, as well as an adjusted net efficiency rating. The adjusted efficiency is a team’s net efficiency, adjusted for strength of opponent and location (home/away/neutral) across all games played. The NET includes more components than just winning percentage.

Late-season games from the 2017-18 season, including from the NCAA tournament, were originally used as test sets to develop a ranking model that used machine learning techniques.

With the changes announced in May 2020, the NET will no longer use winning percentage, adjusted winning percentage and scoring margin. “When we adopted the NET in 2018, we had reviewed several seasons worth of data and we insisted that we would continue to evaluate the metric,” said Dan Gavitt, the NCAA’s senior vice president of basketball. “We’ve been very satisfied with its performance thus far, but it became evident after two seasons of use that this change would be an improvement. While we will continue to monitor the metric, I don’t anticipate any additional adjustments for several years.

In addition, the overall and non-conference strength of schedule has been modernized to reflect a truer measure for how hard it is to defeat opponents. The strength of schedule is based on rating every game on a team's schedule for how hard it would be for an NCAA tournament-caliber team to win. It considers opponent strength and site of each game, assigning each game a difficulty score. Since the NET rankings serve as the primary sorting tool for Division I men's basketball, they play an important role in establishing a team's resume.

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