1,720,959 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
Estimating the population density of insectivorous bats from acoustic recordings with stationary detectors : a case study
No full textDie Schätzung der Dichte von Fledermauspopulationen auf der Basis von aufgenommenen Rufen ist ein Schlüsselthema im Gutachterwesen sowie für Monitoringprogramme, da in diesen Metiers automatische Rufdetektoren gebräuchlich sind und Populationsdichte eine wichtige Variable für entsprechende Beurteilungen sind. Kürzlich entwickelte numerische Modelle erlauben Dichteschätzungen ohne die Voraussetzung der Erkennung der rufenden Individuen. In dieser Arbeit wird ein solches Modell mit empirischen Daten getestet. Wir berechneten die Populationsdichten dreier Arten (Zwergfledermaus Pipistrellus pipistrellus, Nordfledermaus Eptesicus nilssonii und Fransenfledermaus Myotis nattereri) basierend auf automatisch aufgezeichneten Rufen mittels generalized random encounter models (gREMs). Die Validierung unserer Ergebnisse erfolgte (i) durch Vergleich mit bereits publizierten Dichteschätzungen und (ii) mit Royle-Nichols (RN) models, die eine Transformation der Rufaktivitätsdaten auf Präsens-Absenz-Niveau erforderten. Unsere Schätzungen für M. nattereri stimmten mit Literaturdaten und Ergebnissen der RN-models überein. Die Resultate für E. nilssonii wurden von RN-models unterstützt, die publizierten Schätzungen waren doppelt so hoch. Diese Unterschätzung könnte durch die nicht im Modell berücksichtigte Flughöhe der Art verursacht worden sein. Die errechnete Dichte von P. pipistrellus ähnelte Literaturdaten, Ergebnisse der RN-models erreichten allerdings nur ein Zehntel dieser Werte - möglicherweise aufgrund des Informationsverlustes durch die Transformation auf Präsens/Absenz-Daten.Zusammenfassend ermöglichen gREMs vielversprechende Dichteschätzungen von Fledermauspopulationen basierend auf automatisch aufgenommenen Rufen. Allerdings sollten die Flughöhen von Arten in zukünftigen Analysen berücksichtigt werden. Flughöhen könnten in die Berechnung der Detektionsdistanz implementiert werden, um exakte Detektionsbereiche zu berechnen und somit genauere Dichteschätzungen zu erhalten.Estimating the population density of bats using stationary acoustic detectors is a key request of environmental consultants to science, because automated recording units are commonly used for environmental assessments and monitoring programs, and density is an important variable for evaluating impacts. Recently developed numerical methods allow to calculate density estimates from call activity data, even if the recognition of calling individuals is impossible. Here, we tested the applicability of generalized random encounter models (gREMs) for determining population densities of three species (Common pipistrelle Pipistrellus pipistrellus, Northern bat Eptesicus nilssonii, and Natterer’s bat Myotis nattereri) based on passively collected acoustical data. To validate the results, we (i) compared them to density estimates of the species from the literature and to (ii) Royle-Nichols (RN) models of the detection/non-detection-transformed data. Our estimates for M. nattereri matched both the published data and RN-model results. For E. nilssonii, we yielded similar estimates from the gREM and the RN-models, but the published data were more than twice as high. This discrepancy might be caused by E. nilssonii’s high-altitude flight which could not properly be accounted for by the gREM. Results of gREMs for P. pipistrellus were supported by published data but were approximately 10 times higher than those of RN-models – probably an effect of the information loss due to data transformation in RN models that may affect very active species more than less active species.We conclude that gREMs are promising for providing realistic estimates of bat population densities from automatically recorded call activity data. However, the average flight altitude of species should be accounted for in future analyses: We suggest to include flight altitude in the calculation of the detection range in order to assess the detection sphere more accurately and obtain more precise density estimates.Markus MilchramMasterarbeit Universität für Bodenkultur Wien 2019Zusammenfassung in deutscher Sprach
Estimating the population density of insectivorous bats from acoustic recordings with stationary detectors : a case study
No full textDie Schätzung der Dichte von Fledermauspopulationen auf der Basis von aufgenommenen Rufen ist ein Schlüsselthema im Gutachterwesen sowie für Monitoringprogramme, da in diesen Metiers automatische Rufdetektoren gebräuchlich sind und Populationsdichte eine wichtige Variable für entsprechende Beurteilungen sind. Kürzlich entwickelte numerische Modelle erlauben Dichteschätzungen ohne die Voraussetzung der Erkennung der rufenden Individuen. In dieser Arbeit wird ein solches Modell mit empirischen Daten getestet. Wir berechneten die Populationsdichten dreier Arten (Zwergfledermaus Pipistrellus pipistrellus, Nordfledermaus Eptesicus nilssonii und Fransenfledermaus Myotis nattereri) basierend auf automatisch aufgezeichneten Rufen mittels generalized random encounter models (gREMs). Die Validierung unserer Ergebnisse erfolgte (i) durch Vergleich mit bereits publizierten Dichteschätzungen und (ii) mit Royle-Nichols (RN) models, die eine Transformation der Rufaktivitätsdaten auf Präsens-Absenz-Niveau erforderten. Unsere Schätzungen für M. nattereri stimmten mit Literaturdaten und Ergebnissen der RN-models überein. Die Resultate für E. nilssonii wurden von RN-models unterstützt, die publizierten Schätzungen waren doppelt so hoch. Diese Unterschätzung könnte durch die nicht im Modell berücksichtigte Flughöhe der Art verursacht worden sein. Die errechnete Dichte von P. pipistrellus ähnelte Literaturdaten, Ergebnisse der RN-models erreichten allerdings nur ein Zehntel dieser Werte - möglicherweise aufgrund des Informationsverlustes durch die Transformation auf Präsens/Absenz-Daten.Zusammenfassend ermöglichen gREMs vielversprechende Dichteschätzungen von Fledermauspopulationen basierend auf automatisch aufgenommenen Rufen. Allerdings sollten die Flughöhen von Arten in zukünftigen Analysen berücksichtigt werden. Flughöhen könnten in die Berechnung der Detektionsdistanz implementiert werden, um exakte Detektionsbereiche zu berechnen und somit genauere Dichteschätzungen zu erhalten.Estimating the population density of bats using stationary acoustic detectors is a key request of environmental consultants to science, because automated recording units are commonly used for environmental assessments and monitoring programs, and density is an important variable for evaluating impacts. Recently developed numerical methods allow to calculate density estimates from call activity data, even if the recognition of calling individuals is impossible. Here, we tested the applicability of generalized random encounter models (gREMs) for determining population densities of three species (Common pipistrelle Pipistrellus pipistrellus, Northern bat Eptesicus nilssonii, and Natterer’s bat Myotis nattereri) based on passively collected acoustical data. To validate the results, we (i) compared them to density estimates of the species from the literature and to (ii) Royle-Nichols (RN) models of the detection/non-detection-transformed data. Our estimates for M. nattereri matched both the published data and RN-model results. For E. nilssonii, we yielded similar estimates from the gREM and the RN-models, but the published data were more than twice as high. This discrepancy might be caused by E. nilssonii’s high-altitude flight which could not properly be accounted for by the gREM. Results of gREMs for P. pipistrellus were supported by published data but were approximately 10 times higher than those of RN-models – probably an effect of the information loss due to data transformation in RN models that may affect very active species more than less active species.We conclude that gREMs are promising for providing realistic estimates of bat population densities from automatically recorded call activity data. However, the average flight altitude of species should be accounted for in future analyses: We suggest to include flight altitude in the calculation of the detection range in order to assess the detection sphere more accurately and obtain more precise density estimates.Markus MilchramMasterarbeit Universität für Bodenkultur Wien 2019Zusammenfassung in deutscher Sprach
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
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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