If you've been reading this blog, then you'll know that I'm a proponent of M2M defense as your base with selective zone defenses as in-game adjustments or change-ups. I came across this interesting article by John Giannini who is the head coach at La Salle University, providing what appears to be more empirical evidence that M2M is a better base defensive system than zone.

The most common defense is the man-to-man. There has actually been studies done that look at something called the DER -- the defensive efficiency rating. A defensive efficiency rating is 'the number of point scored divided by the number of possessions'. A very good defensive efficiency rating would be 0.75 or lower -- that would be outstanding. People have actually charted multiple games and looked at which defenses have the best defensive efficiency rating and man-to-man usually comes out the highest.
I've never actually charted DER myself, but I think what's interesting about this stat as opposed to field-goal percentage defense or ppga is that it takes a relative measurement based on possessions as opposed to an absolute one. Unfortunately, the article doesn't state where the sources came from, nor does it state the statistical results, but it is still interesting if in fact it proves to be correct -- that the DER stats show that man defense is better than zone as a base.

For more great defensive drills information regardless of whether you are a M2M or zone base, check out Bruce Weber's DVD on 20 Competitive Defensive Drills. Coach Weber is the head coach of the University of Illinois.