As fantasy trade deadlines approach, that's Total Quarterback Rating's advice, particularly if you are in a keeper league.
As you know, QBR evaluates quarterbacks based on their play-by-play contributions to advancing their teams' chances of winning games. This offers a better picture of quarterbacks' overall production than traditional stats, but when I first started looking at QBR's possible fantasy implications, I wasn't sure it would have much to say. On one hand, QBR incorporates a number of factors that help determine whether players stay on the field and score both real-life and fantasy points, like rushing yards, sacks and fumbles. On the other hand, most fantasy scoring systems are tied directly to traditional statistical categories, such as passing yards and touchdowns. It's also not clear just how much quarterbacks' success in high-leverage situations, where QBR awards extra credit, carries over into future fantasy seasons.
As it turns out, QBR is an even better predictor of fantasy value than traditional stats or fantasy stats.
Suppose we look at all quarterbacks who have stayed good enough -- and healthy enough -- to qualify for the NFL passer rating title both last season and this season. Among this group of 25 starters the correlation, or strength of the statistical relationship, between the number of yards they threw for in 2010 and the number of fantasy points they have scored in 2011 is 0.42, or moderately strong.