1,721,031 research outputs found
Changes in the Age Distribution of Mortality Over the 20th Century
Full text linkMortality has declined continuously in the United States over the course of the 20th century, and at relatively constant rates. But the constancy of mortality reductions masks significant heterogeneity by age, cause, and source. Using historical data on death by age and cause, this paper describes the characteristics of mortality decline over the 20th century. Early in the 20th century, mortality declines resulted from public health and economic measures that improved peoples' ability to withstand disease. Because nutrition and public health were more important for the young than the old, mortality reductions were concentrated at younger ages. By mid-century, medical care became more significant and other factors less so. Penicillin and sulfa drugs brought the first mortality reductions at older ages, which were coupled with continuing improvements in health at younger ages. The pattern of mortality reduction was relatively equal by age. In the latter part of the 20th century, death became increasingly medicalized. Cardiovascular disease mortality was prevented in significant part through medical intervention. Most of the additional years added to life in the last few decades of the 20th century were at older ages.
Induced Innovation and Social Inequality: Evidence from Infant Medical Care
Full text linkWe develop a model of induced innovation where research effort is a function of the death rate, and thus the potential to reduce deaths in the population. We also consider potential social consequences that arise from this form of induced innovation based on differences in disease prevalence across population subgroups (i.e. race). Our model yields three empirical predictions. First, initial death rates and subsequent research effort should be positively correlated. Second, research effort should be associated with more rapid mortality declines. Third, as a byproduct of targeting the most common conditions in the population as a whole, induced innovation leads to growth in mortality disparities between minority and majority groups. Using information on infant deaths in the U.S. between 1983 and 1998, we find support for all three empirical predictions. We estimate that induced innovation predicts about 20 percent of declines in infant mortality over this period. At the same time, innovation that occurred in response to the most common causes of death favored the majority racial group in the U.S., whites. We estimate that induced innovation contributed about one third of the rise in the black-white infant mortality ratio during our period of study.
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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