The Total Quarterback Rating is a statistical measure that incorporates the contexts and details of throws and what they mean for wins. It's built from the team level down to the quarterback, where we understand first what each play means to the team, then give credit to the quarterback for what happened on a play based on what he contributed.
At the team level, identifying what wins games is not revolutionary: scoring points and not allowing points. In the 1980s, "The Hidden Game of Football" did some pioneering work on that topic and how yardage relates to points.
We went back and updated what that book did then we went further. At the individual level, more detailed information about what quarterbacks do is really necessary. Brian Burke at AdvancedNFLStats.com has done good work in advancing that effort, and FootballOutsiders.com has done some of this by charting data. And over the past three years ESPN has charted football games in immense detail.
By putting all these ideas together and incorporating division of credit, we have built a metric of quarterback value, the Total Quarterback Rating, Total QBR or QBR for short.