1,720,975 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
Underpinning the precautionary principle with evidence: A spatialconcept for guiding wind power development in endangered species’habitats
Full text linkThe precautionary principle is an essential guideline in decision making, particularly for regulating novel developments with unknown or insufficiently proven environmental impact. However, due to the inherent component of uncertainty it has been widely criticized for being “unscientific”, i.e. hindering progress without sufficient evidence. The consequential postulation, that precautionary measures are only justified if the addressed threats are plausible and the measures reasonable, calls for methods to guide action in the face of uncertainty. Using the example of species conservation versus wind-farm construction, an expanding development with hypothesized – but unexplored – effects on our model species the capercaillie (Tetrao urogallus), we present an approach that aims at compensating the lack of knowledge about the threat itself by making best use of the available knowledge about the object at risk. By systematically combining information drawn from population monitoring and spatial modelling with population ecological thresholds, we identified areas of different functionality and importance to metapopulation persistence and connectivity. We integrated this information into a spatial concept defining four area-categories with different implications for wind power development. Highest priority was assigned to areas covering the spatial and functional requirements of a minimum viable population, i.e. sites where the plausibility for threat is highest, the uncertainty as regards importance for the population is lowest, and thus the justification for precautionary measures is strongest. This gradated approach may also enhance public acceptance, as it attempts to avoid either error-minimization bias (i.e. being too restrictive or permissive) the precautionary principle is frequently criticized for
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
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
Variation in impacts of recreational outdoor activities on wildlife
No full textHuman outdoor recreation activities (i.e. hiking, mountain biking, cross-country skiing) are increasing in numbers, and are economically important in many parts of the world, including the Black Forest. These recreation activities exert pressure on the ecosystems in which they take place and in many cases are a threat to a variety of wildlife species. There are many ways in which wildlife can be impacted by outdoor recreation and tourism: often species react to the presence of humans in a similar way as to the presence of predators, resulting in anti-predator responses. The increase in recreational activities therefore causes an increase in anti-predator costs for wildlife. Some species are attracted to human recreation activities and others have been shown to habituate to human presence, resulting in reduced reactions to humans over time. There are however increasing number of studies indicating negative effects of recreation activities on wildlife. The effects range from fleeing, to changes in vigilance behaviour and reduced use of areas which are intensively used by recreational users (i.e. close to infrastructures such as hiking trails or skiing slopes). Recreation activities have also been linked to changes in bird species composition, reduced densities, and reduced breeding success. Physiological effects include an increased heart rate and increased stress hormone levels in areas close to recreation infrastructure. Previous studies however also revealed that the response wildlife to recreation activities might vary between species, areas and habitats. To provide both possibilities for recreation activities as well as to avoid negative effects on biodiversity, it is important to know the type, extent and source of variation to design effective conservation measures. Using two model species, red deer (Cervus elaphus) and capercaillie (Tetrao urogallus) I studied how the response of wildlife to recreation activities varies under different environmental conditions. From the results I derived management options to mitigate the effects of recreation activities. In the first chapter I analysed GPS telemetry data of red deer to reveal how they have adapted to the diurnal rhythm of recreationists in their habitats. During the day, when recreationists are present, red deer avoid areas close to the recreation infrastructure, however during night, when no recreationists are present; the deer even prefer these areas. This indicates that the deer have temporally adapted their behaviour to avoid human recreationists. At the same time, I was able to show that the deer preferred to use the wildlife refuges (i.e. areas in which recreational activities are prohibited), compared to other management areas. In the second chapter I studied how capercaillie spatially avoided recreational infrastructure in the Black Forest, using radio telemetry. The birds showed reduced use of areas close to recreation activities all year around, with higher avoidance distances in winter (320 m) compared to summer (145 m), resulting in an effective habitat reduction. By including detailed vegetation data in the analysis, I showed that this avoidance distance is reduced when a dense shrub layer is present, i.e. when the hiding possibilities are better. When extrapolating the area affected by recreation infrastructure (within the avoidance distances) to the entire capercaillie distribution in the Black Forest, I revealed that a large fraction of the current capercaillie distribution (i.e. up to 20 % in summer and 40 % in winter) is potentially disturbed by recreational activities. This indicates that local-scale avoidance of recreation infrastructure is likely to cause habitat deterioration on a large scale, possibly negatively affecting the capercaillie population in the Black Forest. By combining the analysis of faecal corticoid metabolites (FCM) with genetic analyses of capercaillie droppings, I was able to reveal the importance of including information on individual heterogeneity in stress responses when studying the effects of recreation activities on wildlife (chapter three). When comparing generalized additive models which included the information on individual heterogeneity (as a random effect) with those not including this information I showed that the results differed greatly. The models without including the data on individual heterogeneity explained only very little (4.0 % and 5.1 %) of the observed variation in FCM-levels. When including the data on individual heterogeneity the explained variation increased significantly (44.0 % and 45.1 %). At the same time the results of the models changed with additional predictors explaining elevated FCM levels appearing significant. The distance to recreation infrastructure was significantly affecting the FCM-levels, with higher FCM-levels close to recreation infrastructure. In this chapter I have demonstrated that individual heterogeneity can explain most of the observed variance in FCM levels and that ignoring this information can lead to erroneous conclusions. In the fourth chapter I combined data from 13 different study areas to evaluate the effect of structural habitat suitability (HSI) on the response of capercaillie to recreation activities on local habitat use, as well as regional population densities. Data on structural habitat parameters and capercaillie habitat use (i.e. droppings, feathers) were collected on sample plots. The probability of finding a capercaillie sign on a plot was positively correlated with the HSI. This probability however was reduced close to recreational infrastructure. Interestingly I found an interaction between the HSI and distance to recreational infrastructure on the local habitat use scale: the avoidance of recreational infrastructures was stronger in poor habitat conditions compared to highly suitable habitats. The regional capercaillie density was also positively correlated to the average HSI in an area, however significantly lower densities were found when over 50 % of the area was potentially influenced by recreation activities. On this scale however, no interaction between the average HSI and recreation infrastructure was found. Increasing the structural habitat suitability might therefore reduce negative effects of recreational activities on a local habitat use scale, but not on a population scale. The fact that I found a threshold, indicates that capercaillie can cope to some extent with recreational activities, however when this threshold is exceeded, there are negative effects on the population. The last chapter synthesizes the results of the previous chapters and shows how these can be applied to mitigate negative effects of recreation on wildlife and systematically designate wildlife refuges, using the example of capercaillie. By applying different research methods, study designs and analysis, my doctoral thesis reveals how the response of wildlife to recreational activities can vary temporally, seasonally, between individuals and under different habitat conditions. I was able to not just generate new insights which are relevant for future researchers in the field of recreation ecology, but also provide results which can be practically applied by practitioners managing nature areas
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