1,721,011 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
The Mesoproterozoic Hallandian event - a region-scale orogenic event in the Fennoscandian Shield
No full textThe Sveconorwegian Province occupies the southwestern part of the Fennoscandian Shield. The easternmost tectonic unit of the Province is the 1710-1660 Ma parautochthonous Eastern Segment, which bears the imprint of at least two metamorphic events; the 1460-1380 Ma Hallandian and the 1150-970 Ma Sveconorwegian. However, the nature and extent of the Hallandian event have been difficult to access due to the Sveconorwegian, effectively masking earlier metamorphic assemblages, structures and relations between rock units.
This thesis aims to characterize the Hallandian event by investigating pre-Sveconorwegian deformation and metamorphism in an area of the Eastern Segment that largely escaped later Sveconorwegian reworking. These results are then considered in a regional perspective and related to ~1.45 Ga magmatism and metamorphism observed elsewhere in Fennoscandia. Considering the compiled data from this time period, it now appears that the Hallandian event indeed was a true orogenic event that affected a large portion of the Fennoscandian Shield.
In the study area, located within the Protogine Zone in the eastern part of the Eastern Segment near Jönköping, Sveconorwegian reworking is restricted to discrete, N-S trending shear-zones. Between these shear-zones, structures, mineral assemblages and geochronological information from pre-Sveconorwegian events are preserved. The first paper provides field, mineral and chemical characteristics, as well as a baddeleyite U-Pb crystallization age of 1455±6 Ma for the Jönköping Anorthositic Suite which is abundant across the study area as small intrusive bodies. In these plagioclase-porphyritic and equigranular anorthositic rocks, deformation is restricted to thin, E-W-trending shear-zones. In the second paper we investigate the deformed country-rocks and date metamorphism and the development of the E-W to SE-NW trending gneissic fabric at 1450-1400 Ma, using U-Pb secondary ion mass spectrometric (ion probe) analysis of complex zircons. The folding event is bracketed between 1440 and 1380 Ma, corresponding to the ages of leucosome formation and the emplacement of a cross-cutting aplitic dyke. In the third paper, the gabbroic Moslätt dolerites are dated at 1269±12 Ma using the U-Pb system in baddeleyite. These have well-preserved magmatic parageneses in contrast to nearby metamorphosed mafic dykes of the 1450-1420 Ma Axamo Dyke Swarm. This precludes the Sveconorwegian event from having caused amphibolite facies metamorphism in the area. In the fourth paper, the first estimate of Hallandian pressure and temperature conditions is obtained from mineral assemblages in one of the E-W-trending shear-zones. Pressure-temperature estimates and hornblende microtextures collectively suggest deformation under conditions of 7-8 kbar and 500-550°C. In the fifth paper we constrain the age of the gneissic fabric in the granitoid country-rock at around 1422 Ma by dating a member of the syn-kinematic felsic Axamo dykes, using the U-Pb ion probe technique. It is suggested that the mafic and plagioclase-porphyritic members of the Axamo Dyke Swarm were emplaced coeval with the Jönköping Anorthositic Suite.
This thesis is the first contribution which recognizes the Hallandian as a regional scale orogenic event, acknowledging all the major features of that age in the Fennoscandian Shield. These features include ~1460 Ma rifting, deposition of clastic sediments and extrusion of continental basalts in central Fennoscandia, 1460-1440 Ma emplacement of I- to A-type granitoids in southern Fennoscandia, 1450-1420 Ma deformation and metamorphism in southern Sweden and on Bornholm, and 1410-1380 Ma post-kinematic pegmatite dykes and intrusions of granite, monzonite and charnockite in the Eastern Segment.
The spatial and temporal trends of these features suggest a tectonic model in which the rifting and mafic magmatism to the north are the far-field effects of north-eastward subduction of an oceanic plate, with the subduction zone located to the southwest of present-day Fennoscandia. Collision with an unknown (micro-) continent led to crustal shortening as Fennoscandia overrode this unknown continent. Post-collisional collapse triggered decompressional melting of heated continental crust, resulting in the emplacement of post-kinematic dykes and plutons
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
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