1,720,981 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
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
Temporal and environmental influences on the vocal behaviour of a nocturnal bird
No full textTemporal and environmental variation in vocal activity can provide information on avian behaviour and call function not available to short-term experimental studies. Intersexual differences in this variation can provide insight into selection effects. Yet factors influencing vocal behaviour have not been assessed in many birds, even those monitored by acoustic methods. This applies to the New Zealand kiwi (Apterygidae), for which call censuses are used extensively in conservation monitoring, yet which have poorly understood acoustic ecology. We investigated little spotted kiwi Apteryx owenii vocal behaviour over 3 yr, measuring influences on vocal activity in both sexes from time of night, season, weather conditions and lunar cycle. We tested hypotheses that call rate variation reflects call function, foraging efficiency, historic predation risk and variability in sound transmission, and that there are inter-sexual differences in call function. Significant seasonal \ud
variation showed that vocalisations were important in kiwi reproduction, and inter-sexual synchronisation of call rates indicated that contact, pair-bonding or resource defence were key functions. All weather variables significantly affected call rates, with elevated calling during increased humidity and ground moisture indicating a relation between vocal activity and foraging conditions. A significant decrease in calling activity on cloudy nights, combined with no moonlight effect, suggests an impact of light pollution in this species. These influences on vocal activity provide insight into kiwi call function, have direct consequences for conservation monitoring of kiwi, and have wider implications in understanding vocal behaviour in a range of nocturnal bird
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
The lek breeding system of the Kākāpō (Strigops habroptilus): the role of vocalisations in female mate choice and kin clustering on leks
No full textFor a species to succeed, individuals must be able to attract a mate. The method in which they do this is known as a breeding system and it involves a diverse array of social behaviours. A lek breeding system is employed by some polygynous species and is characterised by aggregations of males that females visit primarily for breeding purposes. This results in strong sexual selection pressures on the lek, as males compete for females and females ‘choose’ between males. The kākāpō (Strigops habroptilus) is a critically endangered, nocturnal parrot, endemic to New Zealand. Kākāpō are also the only species of parrot with a lek breeding system but female kākāpō only breed every two to five years in response to the masting of rimu (Dacrydium cupressinum) trees. Male kākāpō acoustically and visually display on the lek and are subsequently visited by females. Acoustic displays are an effective method of communication, as components of this display can convey information to females about the quality of a male, thus informing her mate choice. However, little is known about the role that vocalisations play in female kākāpō mate choice or why some males are more successful than others. The first objective of this research was to characterise the three main vocalisations of kākāpō (booms, chings, and skraaks) and investigate their role in female mate choice by analysing the relationship between acoustic parameters and life history traits of male kākāpō using recordings of their vocalisations. Most parameters of vocalisations were not reliable indicators of identity, nor were parameters of vocalisations associated with male reproductive success. Duration and inter-boom/ching duration were the only parameters with sufficient individual variation to signal for identity, but individuals could not be discriminated between based on these two parameters. Vocalisations did not appear to function as honest indicators of age, weight, or origin based on the linear features analysed in this study. There were differences in the dialect of Fiordland kākāpō and Rakiura/Stewart Island and Whenua Hou/Codfish Island kākāpō, but not between those from Rakiura and Whenua Hou. There were temporal patterns between booming and chinging and vocalisations changed over the course of the breeding season. Non-linear phenomena were only present at low frequencies in chings and skraaks. Therefore, the role of male kākāpō vocalisations in female mate choice is still unclear. If vocalisations are not honest signals, females may be using different criteria to select a mate. However, if females are able to recognise males based on the duration and inter-boom/ching duration parameters, they could become attuned to their preferred male, explaining the prevalent skew in reproductive success. A skew in reproductive success is common on leks, which is known as the lek-skew paradox. There are several models, such as the hotspot and hotshot model, that seek to explain why males still gather on a lek despite little or no chance of breeding, which both conclude that males have a greater chance of breeding by gathering on a lek than they would have displaying alone, resolving the lek-skew paradox. Alternatively, males could indirectly benefit by gathering on a lek to increase the reproductive success of a relative (kin selection). However, kākāpō have low genetic diversity, and clustering with kin on a lek could further reduce this. The second objective of this thesis was to investigate the possibility of kin clustering on kākāpō leks using genetic relatedness coefficients. It appears that male kākāpō do not cluster with their kin, and instead, simply migrate to the lek closest to their winter home range whereas female kākāpō visit the largest lek. Both male and female kākāpō also exhibit strong site fidelity and male breeding activity is correlated with the mast level of rimu. Therefore, male kākāpō are not gaining indirect benefits by breeding on a lek and must be gaining direct benefits by exhibiting lekking behaviour, however, what these direct benefits may be is still unknown. When the models used to justify the lek-skew paradox are applied to kākāpō, one single model cannot completely explain this behaviour. It is more likely that a combination of factors are responsible for the maintenance of lekking behaviour in the kākāpō. This study highlights the importance of understanding breeding systems, as this information can have a critical role in the management and conservation of endangered species
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