In the weeks leading up to the NFL Draft, avid fans fill the hours studying the estimated 769,000 mock drafts that exist online, eager to learn who their team will take. But after a few hours of Roger Goodell reading names from a podium, almost all of these mock drafts will prove completely worthless.

To determine just how inaccurate mock drafts are, the Count cross-checked the results of Thursday's first round with the predicted results from 50 prominent mock drafts from draft blogs, national news outlets and local newspapers...