1,720,968 research outputs found
Selection biases within an English football academy: implications of the Elite Player Performance Plan
Full text linkA thesis submitted in partial fulfilment of the requirements of the University of Wolverhampton for the degree of Doctor of Philosophy.The Elite Player Performance Plan (EPPP) was introduced in 2011 in order to enhance the youth football academy system in England. Previous literature demonstrates that relative age and biological maturation are responsible for selection biases within youth football, where both factors exert an influence on anthropometry and physical performances. However, there is limited research that has examined the aforementioned factors over a prolonged period of time, and especially within academies operating under the EPPP. Therefore, the general aim of this thesis was to investigate relative age, biological maturity, anthropometric and physical performance characteristics of male youth players from an English football club, as they progressed through the developmental pathway, under the EPPP framework.
The findings from Chapter 3 revealed that selection within the investigated club was heavily overrepresented by relatively older and earlier maturing players, and this persisted since the EPPP was introduced. Subsequently, Chapter 4 identified that biological maturity, anthropometry and physical performances distinguished players that were retained across the developmental pathway, in an age group dependent manner. Chapter 5 provided estimates for when the development of anthropometric and physical performance characteristics initiate, peak and plateau, according to somatic maturity. Finally, Chapter 6 demonstrated that a bio-banding intervention may influence the decision-making process adopted by academy coaches’ regarding player selection and retention.
In summary, the investigations conducted within this thesis provide novel and contemporary knowledge that can be used to enhance practice within the current club. Specifically, the findings from this thesis highlight that relative age, biological maturity, anthropometry and physical performances influence player selection and retention within this academy, suggesting that policies (e.g. the EPPP) require careful evaluation so that inappropriate selection biases can be nullified. Further studies are required to corroborate and extend these findings on a wider scale through robust methodological approaches
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
Path integration error and adaptable search behaviors in a mantis shrimp
No full textMantis shrimp of the species Neogonodactylus oerstedii occupy small burrows in shallow waters throughout the Caribbean. These animals use path integration, a vector-based navigation strategy, to return to their homes while foraging. Here, we report that path integration in N. oerstedii is prone to error accumulated during outward foraging paths and we describe the search behavior that N. oerstedii employs after it fails to locate its home following the route provided by its path integrator. This search behavior forms continuously expanding, non-oriented loops that are centered near the point of search initiation. The radius of this search is scaled to the animal's positional uncertainty during path integration, improving the effectiveness of the search. The search behaviors exhibited by N. oerstedii bear a striking resemblance to search behaviors in other animals, offering potential avenues for the comparative examination of search behaviors and how they are optimized in disparate taxa.This work was supported by grants from the Air Force Office of Scientific Research under grant number FA9550-18-1-0278 and the University of Maryland, Baltimore County.https://journals.biologists.com/jeb/article/223/14/jeb224618/224529/Path-integration-error-and-adaptable-searc
Polarization Vision of Crustaceans
No full textThis chapter reviews polarization vision in diverse crustaceans with a specific focus on work completed since the 2014 edition of this book. Almost all crustaceans are sensitive to the planar polarization of light. They commonly possess two channels of orthogonally arranged photoreceptors with intrinsically polarization-sensitive ordered microvilli. These two channels are compared to impart linear polarization sensitivity, though ambiguous null points within the system make it impossible to distinguish between different combinations of angles and degrees of polarization. In stomatopods, biological quarter-wave retarders are utilized to bestow circular polarization sensitivity to linear polarization-sensitive photoreceptors, allowing for circular polarization vision—a sensory modality unique to stomatopods so far. Crustaceans occupy a wide variety of environments, each with environmental polarization information that may be used by their inhabitants for a variety of tasks including object detection, navigation and signalling. The celestial polarization pattern viewed underwater through Snell’s window offers one such cue, which some crustaceans, including one stomatopod species, have been shown to use for orientation and navigation. Stomatopods also possess body surfaces that reflect linearly and circularly polarized light that they use for intraspecific communication. Despite the progress in polarization vision research across a variety of crustacean species, many aspects, including post-retinal processing of polarized light, how polarization vision interacts with other visual modalities, and what the evolutionary drivers for this sensory modality are, remain poorly understood. By incorporating new technologies and increasing the breadth of taxa studied, we may gain greater insights into these knowledge gaps and a better understanding of the functional uses of polarization vision beyond navigation and communication
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
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