The foiled underpants bomber, Umar Farouk Abdulmutallab, raises anew the question of how to spot a terrorist. Clear hindsight obscures how hard a task this is. After the 2001 attacks on New York City and Washington, D.C., the German authorities analyzed data for some 8 million potential terrorists living in Germany by a variety of categories and whittled that list down to 1689 individuals, each of whom they hauled in for an interview. Not one turned out to be a threat, according to the social scientists Diego Gambetta and Steffen Hertog in a New Scientist comment.
Gambetta and Hertog mention this and other failed attempts to find good classifiers for profiling terrorist by way of arguing that engineers are three to four times as likely as other graduates to be affiliated with Islamic terrorist groups since 1970. Perhaps, they argue, university subjects provide a key to better classifiers.
Posted by Gregory Wheeler 
