1,721,157 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
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
CONFLICT RESOLUTION THROUGH STRATEGIC VOCAL NEGOTIATION AND COOPERATION IN NESTLING BARN OWLS (TYTOALBA)
No full textLa communication est un aspect fondamental de la vie animale car elle permet la médiation des conflits d’intérêts entre individus, que ce soit pour les ressources limitantes (e.g. nourriture, territoire) ou pour des tâches collectives au sein de groupes sociaux (e.g. recherche de nourriture, défense d’un territoire). L’échange d’informations entre les parties quant à leur capacité, leur besoin et leur motivation à rivaliser permet aux compétiteurs de décider d’entrer dans la compétition, de continuer à s’y investir ou bien de s’y retirer en fonction de leur chance de succès.
Au cours de cette thèse, j’ai exploré différents aspects de la communication vocale, dans le contexte de la compétition pour les proies amenées par les parents, chez les jeunes Chouettes effraies (Tyto alba). Dans ce contexte familial, les poussins ont un intérêt commun pour leurs survies mutuelles puisqu’ils bénéficient de la propagation de leurs gènes en commun (théorie de sélection de parentèle). En l’absence des parents, jusqu’à neufs poussins négocient vocalement entre eux pour l’obtention de la prochaine proie rapportée au nid. Cette négociation a pour but d’informer la fratrie de son niveau de faim, de dissuader les moins affamés de négocier en retour et, par la suite, de quémander la nourriture aux parents à leur retour. Pour cela, les poussins émettent un cri qu’ils font varier en nombre et en durée : un poussin affamé émettant plus, et de plus longs cris qu’un non affamé.
La négociation est un processus dynamique dont chaque étape influence la suivante. Afin d‘améliorer l’issue de la négociation, chaque individu peut stratégiquement ajuster sa communication, en augmentant ou diminuant l’intensité de sa vocalisation en fonction de celle de son rival. Dans un premier temps, nous avons testé, à l’aide de playback interactif, l’efficacité de ces stratégies d’ajustements. Nous avons démontré que pour induire le retrait d’un/e frère/sœur de la compétition, le plus efficace était d’ajuster positivement sa durée de cri à celle de son/sa frère/sœur, tout en ajustant par contre négativement le nombre de cris émis. En d’autres termes, pour dominer une négociation, il est plus efficace de défier son/sa frère/sœur en augmentant simultanément la durée de ses cris. De plus, il est plus efficace de lui laisser l’opportunité de communiquer et d’attendre que celui-ci diminue son nombre de cris pour augmenter le sien. Nous avons également pu démontrer que ces stratégies conduisent le poussin (ici le playback) à émettre plus de cris et de plus longue durée. Démontrer sa motivation requiert donc un investissement plus important, ce qui pourrait aider au maintien de l’honnêteté de cette communication. Les autres stratégies étant moins efficaces, les interactions répétées entre poussins pourraient permettre de renforcer l’aspect coopératif de la négociation. De manière similaire, nous avons montré que les poussins corrigeaient leur frère/sœur lorsque celui/celle-ci ne respectait pas la règle sociale d’alterner ses cris avec ceux de son rival. Corriger ses frères et sœurs pourrait renforcer la stabilité évolutive de la négociation vocale au sein de la fratrie comme un moyen non agressif de se répartir la nourriture.
Dans un second temps nous nous sommes intéressés au rôle que pouvait jouer la négociation pour décider à qui prodiguer un service tel que l’épouillage ou le don de proie. La sélection de parentèle et la réciprocité des services biologiques sont des explications distinctes pour l'origine et le maintien évolutif des comportements coopératifs et de l’altruisme. Bien que considérées comme compatibles, l'interaction entre ces théories et les conditions favorisant la coopération a rarement été testée. Nous avons montré que 1) les poussins les plus âgés et en meilleur condition sont plus enclins à partager la nourriture avec leurs frères et sœurs; 2) le don de proie se produit en particulier lorsque les poussins reçoivent un surplus de nourriture de la part des parents et lorsque la quantité totale de nourriture stockée dans le nid est abondante, c’est donc lorsque le coût de la renonciation à cette proie est faible qu’un poussin la donnera ; 3) le receveur du don de proie est de préférence un frère ou une sœur dans le besoin (le poussin qui négocie le plus avant le don) ou celui qui a le plus coopéré avec le donneur au préalable (le poussin qui a le plus épouillé le donneur).
Cette thèse souligne donc l’importance de considérer la résolution de conflit comme interactive avec des stratégies d’ajustements, de la coopération et des règles sociales. Enfin, la chouette effraie se révèle être une espèce modèle pour l’étude de la communication animale et la résolution des conflits.
--
Communication is a fundamental aspect of animal existence as it mediates survival and reproduction when conflicts of interest occur (over territory, mate or food) or for social integration (acceptation in a group, cooperative behaviour). Assessing a contestant’s relative resource holding potential and motivation to compete through signalling allows individuals to decide whether to engage, to keep competing or to retreat from a contest according to their chances of success.
During this thesis, I investigated various aspects of vocal communication in the context of competition over prey brought by parents in broods of barn owl (Tyto alba). In this family context, nestlings have a common interest in their mutual survival and reproduction since they benefit from the propagation of their shared genes (kin selection theory). In the absence of parents, up to nine nestlings vocally negotiate to get the priority access to the next prey brought by parents. The purpose of this negotiation is to inform siblings about hunger level, dissuade the less hungry siblings from negotiating in return and afterwards from begging when parents arrive. To negotiate, the nestlings emit one type of call that vary in number and duration: a hungry nestling emitting more and longer call than a non-hungry.
Negotiation is a dynamic process with each step of the process affecting the next. To improve its negotiation outcome, each individual can strategically adjust its communication to the contestant’s communication; that is to say, when and how to increase/decrease its vocal intensity according to the contestant’s intensity. We first tested, using interactive playback, the efficiency of these adjustment strategies to the contestant‘s signalling. We demonstrated that the most efficient strategy to deter a sibling from the competition is to match the call duration (increasing and decreasing its call duration simultaneously with the sibling), and to mismatch the number of calls (increasing when the sibling decreases its call rate and reversely). In other words, to dominate a negotiation, it is more efficient to challenge a sibling by simultaneously increasing the call duration. However, it is more efficient to give a sibling the opportunity to communicate by waiting for it to decrease its call rate before increasing its number of calls. We were also able to demonstrate that these strategies lead the nestling (here the playback) to emit more and longer calls. Transmitting motivation to a sibling requires therefore a higher investment which could help maintain this communication honest. Because following other strategies is less efficient to deter a sibling from competing, the repeated interactions between nestlings may reinforce the cooperative aspect of the negotiation. Similarly, we showed that nestlings gave social feedback when a nestling did not respect the social rule of alternating its calls with those of its rival. This social feedback could enhance the evolutionary stability of vocal negotiation within siblings as a non-aggressive way of sharing food.
In a second time, we investigated the role that negotiation could play in deciding with whom to share a prey. Kin selection and the reciprocation of biological services are separate explanations for the origin and evolutionary maintenance of cooperative behaviours and altruism. Although considered as non-mutually exclusive, the cost-to-benefit balance to behave altruistically or reciprocally cooperate, and the conditions promoting a switch between such different strategies have rarely been tested. We showed that 1) older individuals in better conditions are more likely to share food with their siblings than nestlings in poor conditions; 2) the share of prey occurs when the nestlings receive extra food from the parents and the food is abundant, thus especially when the cost to renounce a prey is low; 3) the receiver of the prey donation is preferentially a sibling in need (the nestling who negotiates the most before the donation) or the one who has cooperated the most with the donor beforehand (the nestling that has allopreened the donor the most).
This thesis therefore emphasizes the importance of considering the conflict resolution as an interactive process with strategical adjustment, cooperation and social rules. Finally, barn owls appear to be a key model species for the study of animal communication and conflict resolution
- …
