Some of you are familiar with my writing and have heard of the Positive Impact Factor before. I'll wager that most of you have not and if I'm going to keep using this stat I should explain it in one place that I can refer people back to.
The Positive Impact Factor is an alternative to the Passer Rating that I rolled out in 2010. For starters, the Passer Rating is inconsistent. A perfect rating in college is 1261.6 and 158.3 for the NFL. It is much easier to attain a perfect score using the complicated formula of the NFL as you don't have to throw a 99 yard pass for a touchdown on every play (which is what you seriously have to do to get a perfect passer rating in college). Neither of these rating systems including rushing statistics or receiving statistics. Quarterbacks, especially in college, do more than just throw the ball. The Positive Impact Factor, on the other hand, does include those other stats.
I'll abbreviate the Positive Impact Factor as PIF for the rest of the post. The PIF is based on a 100 point scale and the formula works the same way for the NCAA or NFL. Included in the formula are total touches (pass attempts, rush attempts and receptions), negative plays (incompletions, fumbles and sacks), extremely negative plays (interceptions and fumbles lost) and extremely positive plays (total touchdowns). The basic explanation of the calculation is that the negative plays and extremely negative plays are added together to get a total negative number. The number 100 is subtracted from the negative number and then the extremely positive plays are added to get the PIF number.
Perfect individual games are possible with this rating system (I counted 31 such games in 2010). In individual games a player may also have a PIF number greater than or lesser than 100. Those games are referred to as PIF+ (PIF Plus) and PIF- (PIF Minus) games. To qualify for these exceptional games to be recorded, I set the minimum total touches at 10. The minimum number of total touches per game to make the PIF leaderboard is 14 per game.
Once I have team PIF data in I create team defensive PIF rankings (which are based on the average of all the quarterbacks faced during a season [trick plays don't count]) and create the strength of schedule for individual teams or quarterbacks. This data is used to create an Adjusted PIF ranking where the performances against FCS teams have been removed so we can tell how a team or player did against only FBS competition. There is also not enough games played against FCS to include them in strength of schedule accurately enough for my liking. An Adjusted PIF+ ranking can be determined by multiplying the Adjusted PIF by the strength of schedule.