# College Football 4-team Playoff Probabilites

##### College Football 4-team Playoff Probabilites

We are only one weekend away from finally knowing which four teams will make the inaugural College Football Playoff.  But why wait?  We have game lines out for the key games and we can use implied percentages to make a very educated guess at what teams are going to make it to the semifinals.

I started off with two assumptions:

1. TCU will beat Iowa State
2. Only the top 7 teams in the current playoff ranking have a shot to make the top 4

UPDATE 12/6 (Oregon wins the Pac-12 over Arizona)

There are now four games left to determine who will make the inaugural playoff.  Here are the probabilities of each scenario:

And here’s how the percentages have adjusted with Oregon now pseudo-guaranteed a spot in:

TeamCurrent chance to get in.Chance to get in before Oregon won
TCU91.6%92.9%
Alabama85.5%91.4%
Oregon100%84.1%
Florida State70.3%70.3%
Baylor23.3%29.3%
Ohio State24.6%26.4%
Arizona0%5.6%

Oregon’s win has eliminated Arizona and has made it tougher on the outsiders looking to crash the party.  Florida State’s odds are unchanged as they are essentially in an elimination game; win and they are in, lose and they are out.  There is also a ~15% chance that Alabama could miss the playoff and the vaunted SEC would be left out of the playoff entirely.

Previously Published

With these assumptions, there are five key games that affect the playoffs.  The four Championship games (SEC, ACC, Big Ten, Pac-12) as well as Baylor vs. Kansas State.  There are five games that have two possible outcomes each giving us a total of 32 possible endings to the college football season.  Below is a table of all 32 outcomes with the probability listed of each unique scenario:

Using the current rankings as a guide and by laying a few ground rules, I attempted to determine the four playoff teams for each of the scenarios above.  There were some instances where I had to, um.. well I basically had to guess.  After all, unlike the BCS, the final process is being made by twelve individuals and their opinions instead of mathematical formulas.

First, the ground rules.  If Alabama, Oregon, or Florida State win then they are in.  If Ohio State, Baylor, or Arizona lose then they are out.  I don’t see a legitimate case to be made that a team outside the current top four could lose and still leapfrog their way in.  I also don’t see how Florida State could go undefeated and be left out of the playoff.

With that in mind, here are the chances that each of the following teams ends up in the 4-team playoff:

TeamCurrent chance to get in.Chance to get in before Oregon won
TCU91.6%92.9%
Alabama85.5%91.4%
Oregon100%84.1%
Florida State70.3%70.3%
Baylor23.3%29.3%
Ohio State24.6%26.4%
Arizona0%5.6%

Holy TCU!  With the precedent that the committee has set by putting TCU ahead of Florida State and Baylor, and in addition they have the most winnable game this weekend (34-point favorite), TCU is the most likely team to wind up in the playoff.

Baylor and Ohio State are very close and they were the toughest decisions for me when doing this exercise.  If Oregon loses to Arizona and has 2 losses, do you put in the 1-loss Buckeyes or the 1-loss Bears?  Good luck to the committee.