Not all suicide bombers are created equal, and terrorist leaders know it. According to a new study from the National Bureau of Economic Research, the most spectacular (and technically difficult) suicide attacks are frequently assigned to older and more educated bombers, who are more likely to succeed. Using data collected by the Israeli Security Agency, researchers reviewed all Palestinian suicide attacks against targets in Israel, the West Bank, and the Gaza Strip between September 2000 and August 2005—a total of 151 incidents that killed 515 people and injured almost 3,500 more. Ranking the suicide bombers by the perceived value of their targets (large cities and civilian targets were considered more valuable than smaller cities and military targets) and the number of people they killed and wounded, the researchers found that the five deadliest bombers were almost five years older on average than the typical bomber, that three of them either had or were pursuing advanced degrees (compared with just 17 percent of the sample as a whole), and that all five blew themselves up in major Israeli cities—the most prestigious and challenging of targets. These top five bombers killed an average of 22.8 people per attack and wounded an average of 88, versus 3 and 25.2 respectively for the bombers in the rest of the sample. Overall, younger and less-educated bombers were more likely to detonate too early, get caught by the authorities, or succumb to second thoughts. Human capital, the authors speculate, is the best yardstick for measuring competence at a task in which “on-the-job” training and “learning by doing” don’t figure into the equation.
—“Attack Assignments in Terror Organizations and the Productivity of Suicide Bombers,” Efraim Benmelech (Harvard University) and Claude Berrebi (RAND Corporation), National Bureau of Economic Research
After the last two presidential elections, the predictive power of exit polls has fallen into disrepute. But what about early polls? For Republican primaries, they’re worth watching, a recent analysis by the Pew Research Center suggests; for Democratic primaries and the general election, though, election watchers should be wary of their findings. The authors looked back at nearly half a century of preprimary polling and found that early Republican front-runners are usually safe bets: In seven open GOP contests, the early leaders (the candidates who drew the strongest support in national polls taken more than a year before the general election) won the nomination six times. The same wasn’t true, however, for leading Democrats, who got their party’s nod only 50 percent of the time. In the run-up to the general election, early polling has an even less-impressive predictive record: A review of polls spanning the same period “found many of them forecasting the wrong winner,” and even when they predicted correctly, they were often way off as to the margin of victory. Moreover, the authors note, past precedents are likely to be less relevant to the 2008 election: Front-loaded primaries, early fund-raising events, and multiple potential front-runners make this season’s guessing game harder—and possibly more pointless—than ever.