AIKMAN EFFICIENCY RATINGS:

AEF: To quickly explain his ranking system, he evaluates each team's performance for a game and look at which team has the highest AEF score for that game. Then you see if the highest AEF team won. The score has a high accuracy is "retro-actively" predicting the winner, that is, his system shows what stats are actually contributory in a team winning. The NFL uses total yards (offense, defense) to rank teams, and has a much lower retro-active correlation to winning. The AEF then makes a combined, running tally for the year to determine the 1-26 rankings. It is not intended to predict the winner for future games, but only to show which team has been most effective in doing what they need to do to win.