… One Freedom to Travel member, who also happens to be a tenured mathematics professor, applied something called Bayes Rule and the concept of Base Rate Fallacy to the TSA’s behavior-detection methods… It revealed that even if TSA’s current screening practices were 100 percent effective, only one in 5 million flagged “high risk” passengers would be a terrorist.
“The experience to date is 50,000 false positives and 16 known terrorists not flagged,” says Thomson. “No known terrorists have ever been flagged….” via Sott.net.