1,720,977 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
A NEW SUBSPECIES OF PROECHIMYS-IHERINGI THOMAS (RODENTIA, ECHIMYIDAE) FROM THE STATE OF RIO-DE-JANEIRO, BRAZIL
No full textDescribed a new subspecies of Proechimys iheringi based on specimens collected in the coastal sand plains of the state of Rio de janeiro, southeastern Brazil. This new subspecies can be distinguished by a combination of traits that include an absence of cinnamon ground color in the subapical zone of setiform hairs tail longer than head and body with a whitish brush in the tip, bullae large and well inflated, and by the structure of the septum of the incisive foramen, where the vomer is visible ventrally between the premaxillae and maxillae.58318119
BACULAR VARIATION IN THE SUBGENUS TRINOMYS, GENUS PROECHIMYS (RODENTIA, ECHIMYIDAE)
No full textBacular morphology and variation in the four species of spiny rats of the subgenus Trinomys, genus Proechimys is described. Each species can be uniquely diagnosed on the basis of bacular morphology alone. Proechimys dimidiatus and P. iheringi have similar overall bacular morphology, although they differ noticeably from P. setosus and P. albispinus. The latter two species differ markedly in the morphology of the baculum.57210010
GEOGRAPHIC-VARIATION IN PROECHIMYS-DIMIDATUS (GUENTHER) (RODENTIA, ECHIMYIDAE)
No full textProechimys dimidiatus (Guenther) is an echimyid rodent restricted in distribution to the state of Rio de Janeiro, Brazil. This species was regarded by MOOJEN (1948) to lack geographic variation in pelage, skull, and teeth characters and thus considered monotypic. In the present study, morphometric cranial variation was analyzed in population samples of P. dimidiatus by means of univariate and multivariate procedures. The statistical analyses employed in this paper detected among-locality character variation and population differentiation in P. dimidiatus in spite of the existence of significant within-population variation in skull dimensions. Both univariate and multivariate analyses disclosed no clear geographic trend in cranial character variation in P. dimidiatus. The three populations analyzed were shown to be different in the reduced space of canonical variates, although there seems to be no correlation between morphometric differentiation and geographic distance.2254179538339
CRANIAL INFRASPECIFIC DIFFERENTIATION IN PROECHIMYS-IHERINGI THOMAS (RODENTIA, ECHIMYIDAE)
No full textProechimys iheringi Thomas is an echimyid rodent occurring in eastern Brazil from the states of Bahia to Sao Paulo. MOOJEN (1948) recognized six subspecies of P. iheringi primarily on the basis of clinal variation in the number of cheekteeth counterfolds. In this study we analyzed infraspecific differentiation in 13 morphometric cranial characters in three populations assignable to three subspecies of P. iheringi. Cranial dimensions vary clinally increasing from north to south and morphometric differentiation is correlated with geographic distance. The congruence between the clinal variation in cheekteeth counterfolds and cranial traits indicates that the trinomial nomenclature should not be applied to P. iheringi.561344
THE CONTRIBUTION OF CRANIAL INDETERMINATE GROWTH TO NON-GEOGRAPHIC VARIATION IN ADULT PROECHIMYS-ALBISPINUS (IS GEOFFROY) (RODENTIA, ECHIMYIDAE)
No full textAnalysed the contribution of cranial indeterminate growth in 19 metric characters to intrapopulation variation in Proechimys albispinus (Is. Geoffroy). Individuals were assigned to eight age classes on the basis of tooth eruption and surface wear criteria. The variation in skull characters was partitioned into age and residual components in adult individuals of age classes 6-8. An average of 17.34 percent of the variation in skull traits is due to the age effect in the three combined age classes of adults, and the remaining 82.66 percent accounts for residual variation within age classes. Discriminant function analysis correctly classified 80 percent and 72 percent of individuals to age classes 6 and 7, respectively, whereas all individuals in age class 8 were correctly classified. The implications of these findings for the taxonomy and systematics of the genus Proechimys are discussed.56421922
MULTIVARIATE MORPHOMETRIC ANALYSIS OF SELECTED PROISOTOMA SPECIES (COLLEMBOLA, ISOTOMIDAE)
No full textMultivariate analyses were applied to seven species of the collembolan genus Proisotoma. Principal components analysis and canonical variates analysis resulted in different patterns of ordination. All species, except for P. tenella form a tight cluster in the principal components analysis, whereas three major clusters were produced by canonical variates analysis. The clusters displayed in the reduced space of canonical variates are concordant, in part, with groupings based on a different set of morphologic characters and may have systematic significance.227416719810
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