1,720,961 research outputs found
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
Data and code for 'Disease shrinks metapopulation viability for amphibians'
No full text<p>This repository provides all data and R code from the analysis presented in the following paper:</p>
<p>Heard, G.W., Scroggie, M.P., Hollanders, M., and Scheele, B.C. (in review). Disease-induced mortality shrinks metapopulation viability for amphibians. </p>
<p>The data are provided as a series of .csv files. A GRD file is provided for the landscape rasters. R code is provided separately for each of the following components:</p>
<p>1. A script to complete regression modelling of age structure data for populations of the focal species pre- and post-Bd, plus estimation of adult survival rates from the age structure data using the 'catch curve' approach ('Age_structure_analysis.R').</p>
<p>2. A script to generate the sample landscapes used for simulations of metapopulation dynamics for the pre- and post-Bd epochs ('Derive_landscape_rasters.R').</p>
<p>3. A script with functions for simulating metapopulation dynamics with the aid of the STEPS R package ('STEPS_model.R').</p>
<p>4. A script to run the metapopulation simulations across all the demographic and connectivity scenarios, where connectivity scenarios are defined by the sample landscapes ('Run_STEPS_simulations.R'). </p>
<p>5. A script to fit logistic regression models to the outcomes of the metapopulation simulations (extinction versus persistence) ('Metapop_sims_analysis_GLM.R').</p>
<p>6. A script to fit multivariate normal hypervolumes to the outcomes of the metapopulation simulations (extinction versus persistence) ('Metapop_sims_analysis_MVNH.R').</p>
<p>In combination, the data files and scripts allow all analyses from the paper to be reproduced. </p>
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
Zonal hybridization in frogs of the Geocrinia laevis complex (Anura: Myobatrachidae) : population ecology and male acoustic behaviour
No full textTypescript (photocopy)Author's name on spine: M. ScroggieThesis (PhD) -- University of Melbourne, Faculty of Science, 2002Includes bibliographical references (leaves 193-214)Population ecology, life-history variation and the vocal behaviour of males were investigated in allopatric populations of two species of myobatrachid frogs (Geocrinia laevis and G. victoriana) and within a hybrid zone between the species.
The skeletochronological method was shown to be a reliable and accurate method for age- determination of frogs of the Geocrinia laevis complex. Population age-frequency data from four study populations obtained using skeletochronology allowed estimation of age at maturity, adult survival-rates and age-specific fecundity in populations of the two species, and in two hybrid zone populations. In all four study populations the age at maturity was 2 years post-zygote for both males and females. Estimated annual rates of survival among adults were less than 0.5 in all populations, with males having slightly lower rates of survival than females. The maximum observed longevity was 5 years post-zygote.
The measures of age-specific survival and fecundity for females from the four populations were used to construct matrix models of the populations. Elasticity analysis of these models revealed that rates-of-increase of the populations are expected to be particularly sensitive to perturbations in survival rates of juveniles and larvae.
Females of the G. laevis complex were found to invest heavily in reproductive output, with the level of reproductive effort (expressed as relative clutch mass) among the highest of any anuran for which comparable data are available. Maternal body-size was positively correlated with the numbers and sizes of eggs contained in clutches. Significant differences were detected among populations in the sizes of the eggs produced, independent of effects of maternal body-size.
Notwithstanding the differences which were observed between populations in egg-size, little evidence of differentiation in life-history traits was detected between the study populations of the two species and their hybrids. Hence it was concluded that interpopulational variation in life- history traits is of very limited significance to the dynamics and structure of the south-western Victorian hybrid zone between G. laevis and G. victoriana.
Measurements of the mating success of individual males from populations of both parental species, and from a hybrid zone population, did not reveal any consistent effects of male body-size on mating success. Within a hybrid-zone population, the attributes of advertisement-calls of males were not predictive of their mating success.
The territorial vocal behaviour of male hybrids was assessed. It was found that most hybrid males possess encounter calls functionally equivalent to those of G. victoriana, evoked by exposure to advertisement calls presented at high intensity. The responses to hybrid males during simulated territorial interactions were not related to a phenotypic index of hybridity, suggesting genetic and functional decoupling of the two components of the vocal repertoire (advertisement calls and encounter calls) among hybrid-zone males. This decoupling of the components of the vocal repertoire may be the result of selection on the vocal behaviour of males within hybrid populations.
It is concluded that sexual selection on the vocal behaviour of males within the hybrid zone is probably a crucial factor in determining the dynamics of hybridization in the G. laevis complex
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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