Defensive Efficiency

[RynMan]

I have been looking at this stat lately and was wondering if you guys could answer a couple of questions regarding this statistic.

I understand that DE basically quantifies how well a team converts balls put into play, into outs. My question is does this statistic basically work on the theory that hits are, alot of the time, based on luck? Because if one team has starters that don't allow much solid contact, essentially making it easier for the defense to field balls into play - doesn't that assist in the team's DE? Of course one can't control for things like contact, but is Defensive Efficiency a legitimate stat in evaluating a team's defense, or do you think a pitching staff really does have alot more to do with it?

[RynMan]

Or is the pitcher basically included in this statistic, as how well he induces grounders etc is actually considered part of the defense? The whole defense - pitcher and the team behind, are one machine and this stat tells you how effective they work together to turn balls into play, into outs....?

[rotterdam_82]

All pitchers, over the course of their career, allow the same percentage of 'balls in play'. The only modern day hurler to defy this logic is Greg Maddux.

I think the number is .298. I don't know if that helps at all?

And yes, they do take into account FB/GB numbers.....

[Amazinz]

This statistic looks at the rotation and the defense as a unit. The rotation's line drive rate, for instance, and other factors will affect how difficult it will be for the defense to convert a BIP. Most of the time this stat is listed along with the DER per pitcher.