I wanted to take a look at Georgia Tech's past season game by game to try get a better picture of how GT did than just saying our season was a disappointment. With the new excellent SBNation blog Football Study Hall football fans are able to learn more about their teams and the game of football than ever through the use of statistical analysis. As a Georgia Tech student this fits me perfectly. Football Study Hall introduced a concept called Equivalent Points. Equivalent Points tabulates all the results from each play for a college football season and assigns a point value for each yard line based on the average points scored when teams had the ball on that yard line. For a better explanation go here. I took the list of EqPoints and started charting Georgia Tech's game against Kansas using the play by play data. Here is what a sample drive looked like using the point values:
What this allows me to do it to take every play from a game and assign to it a point value for the amount of yards gained. However, Equivalent Points only takes into account the field position change. I say field position change instead of yardage change because Equivalent Points does take into account that a 10 yard gain from your opponent's 20 is worth more than a 10 yard gain from your own 20. This means Equivalent Points has no context, it does not matter what down it is or what distance it is or how much time is left on the clock, it is just the equivalent points expected from possessing the ball at that yard line, which is still very valuable information. With this information we can tabulate Georgia Tech's expected points for an entire game based on its change of field position. Here are the results:
While the total points is pretty close to the 25 we actually scored this number does not take into account turnovers and I am still unsure of how to use the data correctly. What I am more interested is the per play breakdown. Obviously our bread and butter is the run and it is reflected both in how many plays we ran, 51 runs to 16 passes, and the total points we accrued, 18.43 to 6.49. However, when looking at our per play numbers we actually earned more points per pass play than per run play. Alot of this can be credited to 2 passes, a 46 yard pass to Embry Peeples from our own 4 worth 1.268 points and a 40 yard touchdown pass on the same drive to Stephen Hill worth 4.343 points. With out those two passes our Equivalent Pass Points drops to about -.1 points. Again, this makes sense, we have a very high risk high reward passing game. While I very much enjoy this type of analysis and making these write-ups I do realize that there is very little context for these numbers. Equivalent Points does not take into account down, distance, or game clock. It is merely an average of the points gained from a team simply possessing the ball at that yard line. Luckily Football Study Hall has given us 2nd level Equivalent Points which take into account the down that the play is on as well as the yard line. Lets take a look at the same categories as before:
2nd Level Equivalent Points are much more volatile than 1st level, after looking at the data it appears that the biggest swings in points is from gaining a 1st down. This does make sense, converting for a new set of downs gives the offense 3 more chances to score before they have to decide if they want to go for it. Maintaining those chances is in essence the main goal of an offense, continuing to get chances to score. What can we learn from this data? Our predominately rushing offense seems to do a good job on first down to set us up for successful conversions on 2nd and 3rd down, as opposed to actually converting for a new set of downs on 1st down. Other than that, I really do not know. Perhaps PJ is right by being so gutsy on 4th down? 2nd level points seem to reward him for converting a good percentage of these 4th downs. What do you guys think? If you have any questions or want more information comment below and I will try and discuss things with you as best I can. I plan on doing this for every D1 game we played this year and if I have the time or energy I will do the defense as well. I encourage anyone who is interested on Equivalent Points to read up on them and start game charting on your own. It is a great way to pass the time until there is real football to watch.
Here are the breakdowns player by player:
As you can see Nesbitt is pretty important, it will be interesting to see the differences between Nesbitt and Washington.