1,720,960 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
Transboundary threats in the Mekong basin: protecting a crucial fishery
Get PDFThis repository item contains a single issue of Issues in Brief, a series of policy briefs that began publishing in 2008 by the Boston University Frederick S. Pardee Center for the Study of the Longer-Range Future.In this Issues in Brief, Pardee Center Visiting Research Fellow Irit Altman looks at the impacts that dams in the upper Mekong River basin have on the critically important fishery in Cambodia’s Tonle Sap, the largest freshwater lake in Southeast Asia. Altman explores how development of dams, in combination with a failure of regional governance, has threatened the ecological sustainability of the lake and its watershed, and the livelihoods of people in the region. She identifies strategies to enhance the resilience of the Tonle Sap fishery and improve the lives of people who are connected to this unique ecosystem.
Irit Altman is a Pardee Center Visiting Research Fellow and Research Assistant Professor of Biology at Boston University. A marine and freshwater ecologist, she works with an interdisciplinary research team to develop ecosystem models that integrate scientific knowledge and inform decision-making. She has extensive experience working with field experts and decision makers in Cambodia to understand system change and explore sustainability options in the Tonle Sap ecosystem
Trematode parasites of the mudsnail Ilyanassa obsoleta: An analysis of parasite communities at different scales
Get PDFThis research examines the ecological factors that shape trematode parasite communities of mudsnail Ilyanassa obsoleta at three different spatial scales. Nine species of trematode which obligately infect I. obsoleta during larval stages but use numerous estuarine species as second intermediate and definitive hosts are considered. The work provides the most geographically extensive examination to date of this trematode parasite community.
At the broadest scale, I. obsoleta trematodes were examined across their distributional range (Chapter 2) which includes both native and introduced populations. The results demonstrate that introduced trematode communities are characterized by lower abundance and diversity compared to native communities and therefore conform to the pattern predicted by the enemy release hypothesis. The ecological factors that contribute to the establishment of specific L. obsoleta trematodes in the introduced range are considered.
A regional scale analysis of I. obsoleta trematode communities is presented in Chapter 3. Trematode abundance and diversity along with a wide variety of biological, chemical, and physical factors was examined at fifteen salt marsh sites located throughout northern New England, USA. Although the abundance of numerous hosts were measured as part of this work, variables found to be most strongly correlated with trematode abundance and diversity at sites (revealed through multiple regression analysis) were of physical and chemical origin including sediment nitrogen, roads, trace metals and the distance of sites from the ocean. The results are explored in the context of a variety of candidate mechanisms.
Chapter 4 focuses on I. obsoleta trematodes at a local scale within a single salt marsh site. The work examines intra- and inter-annual patterns of trematode infection in snails associated with four distinct salt marsh habitat types. Experiments were conducted to assess the importance of key processes in determining infection patterns including acquisition of infection by I. obsoleta, mortality, movement, and demographics of the snail hosts. Results indicate that patterns of infection among the salt marsh habitats are subject to strong shifts over time. Changing demographics and snail movement (but not infection input) are likely to be the strongest factors contributing to changing infection patterns across habitats in this system
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Mapping Ecosystem Service Flows in Cambodia\u27s Great Lake Tonle Sap: Data and Knowledge Integration to Understand Fish Production and Biodiversity in Southeast Asia\u27s Most Important Freshwater Ecosystem
No full textMarine and freshwater ecosystem-based management is an integrated approach that requires understanding how key spatial and temporal linkages support flows of ecosystem services (i.e., the benefits that human\u27s derive from the natural world) across a relevant geography. While there currently exists much research on mapping single system features or processes in aquatic environments (e.g. bathymetry, sediments, biogenic habitat), identifying connections across data layers to explore the origins and flow of ecosystem services (e.g., maintenance of natural species\u27 communities, delivery of economic opportunities, access to food and nutrition resources) is less often pursued due to challenges of uncertainty, multiple scales, and the need for cross-disciplinary thinking. At the same time, it is just this type of integrated thinking and analysis that is needed to support sustainable decision making in aquatic systems where the goal is to protect, maintain, and restore ecosystem integrity over the longterm.
In this talk, I present a conceptual and analytical approach for linking various types of spatial and temporal data within an ecosystem service modeling framework. The approach has been applied to marine and freshwater case studies in Belize, Massachusetts, and Cambodia and in each system our team has integrated across informational sources including remotely sensed imagery, seafloor mapping, regional- and local-scale monitoring data, and expert knowledge. I will focus most closely on the ongoing integrated modeling work for Cambodia\u27s Great Lake Tonle Sap. Often called the, \u27beating heart of Cambodia,\u27 Lake Tonle Sap is fed by the seasonal monsoons of the Mekong Basin and exhibits an annual flood cycle that increases the inundated lake by six-fold (from 2,500-15,000 km2). This \u27flood pulse\u27 is a predictable feature of the ecosystem and contributes to high levels of biological productivity and diversity. Specifically, the Lake in the primary contributor to Cambodia\u27s inland fish catch which has been estimated at 230-360 thousand tons in recent years. Furthermore, the lake and surrounding watershed are known to support diversity of fish (\u3e400 species) and tetrapods, of which ~20% experience some level of threat. Our work is integrating a variety of data on this system including digital elevation maps, hydrological time series, remotely sensed landuse/landcover (LULC), and expert knowledge on suitable habitat for different species. Using rules about flooding and LULC, we predict the availability of important fish and tetrapod habitat under different management scenarios and explore changes in relative production of these groups. Changes in ecosystem services are considered in the context of the health and wellbeing of human populations that live on and around the Great Lake.
Presenter Bio
Irit Altman is a Research Scientist at Boston University with expertise in community ecology, ecological parasitology, ecosystem service modeling, and ecosystem-based management. She received her Ph.D. in 2010 from the University of New Hampshire where her research focused on understanding patterns of marine trematode parasite communities at multiple spatial scales. With an extensive background in marine field studies, Irit has been working most recently with a team of researchers to develop models of ecosystem service flows that support sustainable decision making. Ecosystem service models provide a platform for data integration, hypothesis development, decision support, and stakeholder engagement and can support adaptive management over the longterm
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