Early Paleoindian Mobility and Watercraft: An Assessment from the Mississippi River Valley

Several researchers have suggested use of watercraft during the Early Paleoindian period 11,500 and 10,800 rcybp (13,400–12,700 cal B.P.), but none have brought empirical data to bear on this possibility. This paper addresses the potential for fluted point-making groups to have made and used boats circa 11,000 rcybp (13,000–12,800 cal B.P.). Fluted point data from a large region of the upper and central Mississippi River valley strongly suggest that the Mississippi River was a barrier to movement and that Early Paleoindians in the midcontinent did not routinely use watercraft.     

Learning from Schools: School Choice,Political Learning,and Policy Feedback

This article investigates the policy feedback and political learning effects of school vouchers. Of particular interest is how market‐based policies affect the likelihood that program participants will connect their experiences with the policy to the government. I examine parent survey data from an evaluation of the Milwaukee school voucher program. I find that voucher parents are more likely than public school parents to perceive that the government has influenced their child's schooling and to believe that their experiences with their child's school have taught them about how government works. Further, voucher parents report that their experiences with the policy have made them more politically active. While majorities of voucher and public school parents support increased public school expenditures, there is some evidence that school vouchers may decrease support for public schools.     

The Importance of Attention Diversity and How to Measure It

Studies of political attention often focus on attention to a single issue, such as front‐page coverage of the economy. However, examining attention to a single issue without accounting for the agenda as a whole can lead to faulty assumptions. One solution is to consider the diversity of attention; that is, how narrowly or widely attention is distributed across items (e.g., issues on an agenda or, at a lower level, frames in an issue debate). Attention diversity is an important variable in its own right, offering insight into how agendas vary in their accessibility to policy problems and perspectives. Yet despite the importance of attention diversity, we lack a standard for how best to measure it. This paper focuses on the four most commonly used measures: the inverse Herfindahl Index, Shannon's H, and their normalized versions. We discuss the purposes of these measures and compare them through simulations and using three real‐world datasets. We conclude that both Shannon's H and its normalized form are better measures, minimizing the danger of spurious findings that could result from the less sensitive Herfindahl measures. The choice between the Shannon's H measures should be made based on whether variance in the total number of possible items (e.g., issues) is meaningful.     

A History of Depressed Skull Fractures from Ancient Times to 1800

The story of managing depressed fractures illustrates how knowledge of proven value does not always get handed down. Celsus was the first to describe sensible management for depressed fractures. As he wrote in Latin this was forgotten. Galen’s Greek writings survived forming the basis of management until the sixteenth century. In 1517, Hans von Gersdorff published a formidable illustrated surgical text. One illustration depicts an instrument for elevating depressed bone fragments. It looked dramatic but could not work and its defects were finally defined in the eighteenth century. Ambroise Paré used a bone punch just as we do today, but no later surgeon mentions this, though the instrument was well known. Elements of chance, fashion, emotionally powerful illustrations, and perhaps stubbornness had a profound effect on management delaying rational treatment for centuries.     

A Transnational Perspective on Psychosurgery: Beyond Portugal and the United States

The history of psychosurgery is most often recounted as a narrative wherein Portuguese and American physicians play the leading role. It is a traditional narrative in which the United States and, at times, Portugal are central in the development and spread of psychosurgery. Here we largely abandon the archetypal narrative and provide one of the first transnational accounts of psychosurgery to demonstrate the existence of a global psychosurgical community in which more than 40 countries participated, bolstered, critiqued, modified and heralded the treatment. From its inception in 1935 until its decline in the mid-1960s, psychosurgery was performed on almost all continents. Rather than being a phenomenon isolated to the United States and Portugal, it became a truly transnational movement.