Back in January, we wrote a series of three articles on Real Quarterback Rating Differential, and its value in predicting winners and losers in the NFL. By incorporating all quarterback stats, including rushing plays and fumbles, not just their passing stats, it improved upon the predictive value of quarterback rating differential.
The current passer rating is just that, a measure of passing effectiveness. Real Quarterback Rating includes rushing attempts, rushing yards, rushing TDs, fumbles and sacks to produce a new kind of rating that measures a quarterback’s overall performance with the ball, not just as a passer when he actually releases the ball (which is all that passer rating currently measures).