"The new, invasive passenger screenings at airports are more than just expensive and unsettling. They decrease the chances of finding a problem and averting an attack!
The transportation security (TSA) government agents are tasked with detecting a very uncommon event--the one among millions of passengers who intends to do harm and who has the capacity to succeed. A notable new line of defense the TSA is rolling out, which is also its most expensive and ineffective one, is the physical examination of passengers at airport security checkpoints.
It is well known in psychology, but evidently unknown in government, that rare events--that is, very low frequency events like a passenger with explosive underwear--are very hard to accurately perceive. Watching passengers day after day after day, human screeners are very likely to miss seeing objects that very rarely appear. So the best way to make TSA agents ever less likely to succeed in finding such a threat is to make them screen huge numbers of passengers.
There's more. With such massive screening, there will also be many "false positives"--that is, cases in which a potential threat is identified but turns out to be not really a problem. The TSA agents will find harmless prosthetics, medical implants, deformities, illnesses, personal idiosyncrasies, and a whole host of similar variations. After extensive follow-up, the people thus singled out will be allowed through to the airplane. But the TSA agents will see so many cases of these false alarms, these false positives, that it will interfere further with their ability to recognize the true threats".
Read more;
http://www.psychologytoday.com/blog/secrets-longevity/201011/scientific-reasons-not-screening-all-airline-passengersI believe these screenings are not only a violation of our rights, but a waste of time.