The amount of data generated by SportVU can overwhelm NBA executives. Illustration by Bryan Christie for ESPN The Magazine

This story appears in the June 27, 2011 issue of ESPN The Magazine.

LIKE CORPORATIONS AND SEX VIDEOS, sports stats are divided into two categories: public and private. Public numbers -- box scores and the like -- are for fans; we scrutinize them in the hope of better understanding teams and players. (And if we happen to win our fantasy leagues? Gravy!)

Private stats, though, are for team brass only. Those metrics -- which can illustrate how Kevin Durant's shooting percentage drops to single-digit territory when he dribbles too much or how many of Zach Randolph's rebounds are uncontested -- are as proprietary as a Google algorithm. That public/private divide is one reason fans don't understand the rationale
behind team decisions and why GMs are so quick to dismiss second-guessers. The two parties aren't even working off the same data.