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Relationships between the subligurian allochton and the Tuscan foredeep turbidites in the Bobbio Window (NW Appennines).
No full textCalcareous nannofossil biostratigraphy of the Bobbio Formation (NW Apennines, Italy).
No full textThe Bobbio Formation, traditionally subdivided into two lithological members: the Brugnello Shale (lower member) and the San Salvatore Sandstone (upper member), occurs in the core of the Bobbio tectonic window located 50 Km SW of Piacenza (Italy). It is covered tectonically by allochtonous units thrust toward the NE and is considered as the northwestern-most surface occurrence of the Cervarola Sandstone.
Here we report the results of a systematic and quantitative study of the calcareous nannofossils carried out in the frame of a mapping at the 1:10.000 scale of the Bobbio window area. The calcareous nannofossils from the Bobbio Formation are represented well enough for biostratigraphic and chronostratigraphic interpretation although the biostratigraphic signal appears strongly noised. The integration of the paleontological data with the field informations has allowed the interpretation of the chronology of the Bobbio Formation. The calcareous nannofossils indicate an early Miocene age for the entire Bobbio Formation. In fact, the Brugnello Shale is Aquitanian - early Burdigalian and the San Salvatore Sandstone is late Burdigalian (the San Salvatore Sandstone contains in its lower part Sphenolithus belemnos while Sphenolithus heteromorphus is missing). According to the most recent calibration of calcareous nannofossil events, the turbidites of the San Salvatore Sandstone were deposited between 19.4 Ma and about 18 Ma at a minimum average sediment accumulation rate of the order of 140 cm/Ky (compacted thickness)
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
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