Evaluation of cast methods for estimating age from the os pubis.

Age-related changes of the pubic symphysis have gained wide acceptance among physical anthropologists as one basis for estimating adult skeletal age. However, these methods have not been tested by independent observers on large samples with known ages at death that represent contemporary populations. In this study 202 female and 116 male pairs of pubes collected at autopsy were blindly evaluated for age using the McKern-Stewart or Gilbert-McKern and Suchey-Brooks methods. Performance of the methods was measured by mean absolute deviation of true age from scored interval means and frequencies of true age falling within +/- 1 and +/- 2 standard deviations from the mean. The results suggest that the Suchey-Brooks methods are superior in forensic applications and that the racially specific refinement for males should be used. Age estimates should include +/- 2 standard deviations, and chances of error should be considered, especially when advanced age or debilitation is suspected.     

Substituting the End for the Whole: Why Voters Respond Primarily to the Election‐Year Economy

According to numerous studies, the election‐year economy influences presidential election results far more than cumulative growth throughout the term. Here we describe a series of surveys and experiments that point to an intriguing explanation for this pattern that runs contrary to standard political science explanations, but one that accords with a large psychological literature. Voters, we find, actually intend to judge presidents on cumulative growth. However, since that characteristic is not readily available to them, voters inadvertently substitute election‐year performance because it is more easily accessible. This “end‐heuristic” explanation for voters’ election‐year emphasis reflects a general tendency for people to simplify retrospective assessments by substituting conditions at the end for the whole. The end‐heuristic explanation also suggests a remedy, a way to align voters’ actions with their intentions. Providing people with the attribute they are seeking—cumulative growth—eliminates the election‐year emphasis.     

Choose Your Weapon: The Impact of Strategic Considerations and Resource Constraints on Terrorist Group Weapon Selection

ABSTRACT

Historians of terrorism note that modern terrorists rely almost exclusively on two weapon types: the gun and the bomb. However, the comparative use of these weapons differs from one terrorist group to the next. We exploit this variation to examine how the tactical decisions of terrorists respond to both strategic aspirations and resource constraints. We argue that a group’s goals (a strategic consideration) and size (a resource constraint) provide a parsimonious explanation for weapon selection. Because firearms inherently expose the shooter to higher risk, are more precise, and must be used if a group aspires to maintain social order, they are unlikely to be used by groups with limited recruits in a campaign of violence. We test this theory using data on over 350 terrorist organizations. Our analysis shows that strategic considerations and resource constraints both impact tactical choices, although groups with the most expansive goals, those which transcend national borders, as well as militias, are two interesting exceptions to our theory. Our research has implications for the use of disaggregated tactical data and in furthering our understanding of the rationality of terrorism.