The How of a Computer Ranking System

I cannot divulge every secret of my ranking system, or then anybody could just copy what I did. So, I am just going show you basically how it works.

First, I had to develop how the teams would be compared. I had some ideas like, compare rankings, compare wins and loses, compare score, compare defense, and etc. So, I tried to combine many of these comparisons into the current version of my rankings. Most of the major team statistical categories are compared.

• Scoring offense and defense
• Running offense and defense
• Passing offense and defense
• Time of possession
• Fumbles
• Interceptions
• First Downs

To compare these categories, the current game against an opponent is compared to the average of that opponent. Lets say, Michigan St. usually gives up 14 points a game, over 5 games. Then on their sixth game, Purdue scores 27 points on them Michigan St. will receive (14/27)*weight for that game. Then to find Michigan state's rank all the statistical weighted averages are summed.

Also, where a game is played (location) and when a game is played (date) will determine the win loss record as well. If a team wins more on the road then they are given more points than winning at home. Just as losing at home costs more points than losing on the road. Similarly, late season wins and loses help or hurt more than early season wins and loses.

The weights are a work in progress as well. Right now I feel that they are set at a good level. The category with they highest weight is wins and loses. It really doesn't matter how good your stats are if you never win any games. This accounts for almost half of the weighting. Next is scoring defense and then offense, followed by run defense and offense. The weights trail off after that.

That is pretty much how the rankings work. Later I will show you an example of using last years statistics.

The What of a Computer Ranking System

Now, the "What" of the computer ranking system is not to tricky to convey. The "How", which is more tricky, will come later but the what is more of a statement. A computer ranking system compiles statistics from games played throughout the season to find which team is the best. There are many computer rankings out there:

Sagarin
Massey
CFRC
Many Others (listing of all the rankings, and how accurate they are)

The Massey ranking is actually a compilation of about 100 ranking systems and then averaged out. I think that is a great way to do it, but that doesn't make you really the author of one of these rankings. That just makes you the one who takes an average of 100 numbers.

The Many Others link I find very interesting. This site (which looks Russian) actually tests to see which ranking system is the best. Now I would love to make it near the top of that site. That is definitely an interesting site, and too bad I don't know Russian. Dig around awhile, it is a good read.

Also, many rankings want to be predictive in nature and that is not what my ranking is about. I don't really care who wins next week. I want to know who is the best now. That might be a good benefit of having a ranking system, but not the purpose. As well, many rankings include strength of schedule. Currently this is not included in my rankings, and I have thought about adding it, but not a high priority.

My ranking system is based upon mostly, score, offensive and defensive statistics verse the opponents averages, date, and where the game is played. I feel these are the most important factors to find out which team is the best. So what...

The Why of a Computer Ranking System

The idea of a computer ranking system first popped into my head at the end of the college football season last year. While walking around Georgia Tech's campus I wanted some way to connect all the college football teams, through statistics, to find which team was the best. Now, I know there are many different computer rankings out there, not to mention all the human polls as well. But, I wanted something that I had created to compare to all these other systems of trying to determine who is the best.

There are many different things that caused me to come up with a computer ranking system. Not trusting the others, seeing if I could actually implement a ranking system, the push (or really just the snickers) of friends, as well as other things. But, I wanted something that was completely interconnected. Where teams would be compared on many different levels and to their different opponents. So, hopefully these rankings that I have developed will do all these things. Probably not, but oh well, it has been fun and I am sure it will get even better as I try them out this first year.

Inagural Ballot Post

I guess I should probably explain what this blog is for here in the introductory post. This blog will consist of the progress of a College Football computer rankings system. The background of how and why this system was developed will be explained fully in later posts. But, this blog will show you, the loyal reader of this blog, what the outcomes of my computer rankings are, how I am implementing the rankings, comparison to other rankings and polls, as well as any other College Football thoughts or news that I deem worthy of putting on this site. I hope that reading this blog will be semi-insightful, and if not, oh well. So, I am going to give it a try.

-Ben