Randomly Wrong

Copyright 1999 by Paul Niquette. All rights reserved.

Dr. Theodore P. Hill asks his mathematics students at the Georgia Institute of Technology to go home and either flip a coin 200 times and record the results, or merely pretend to flip a coin and fake 200 results. 

The following day he quickly scans the homework data, and to the students' amazement, he easily fingers nearly all those who faked their tosses. 

"The truth is," he said in an interview with the New York Times, "most people don't know the real odds of such an exercise, so they can't fake data convincingly."

What is the secret?