63 resultados para SCIENTOMETRICS


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The publications in scientometrics and bibliometrics with Brazilian authorship expanded exponentially in the 1990-2006 period, reaching 13 times in the Web of Science database and 19.5 times in the Google Scholar database. This increase is rather superior to that of the total Brazilian scientific production in the same time period (5.6 times in the Web of Science). Some characteristics to be noticed in this rise are: 1) The total number of articles during this period was 197; in that, 78% were published in 57 Brazilian journals and 22% in 13 international journals. 2) The national and international articles averaged 4.3 and 5.9 citations/article, respectively; two journals stood out among these, the national Ciencia da Informacao (44 articles averaging 6.7 citations/article) and the international Scientometrics (32 articles averaging 6.2 citations/article). 3) The articles encompass an impressive participation of authors from areas other than information science; only one-fourth of the authors are bound to the information science field, the remaining ones being distributed among the areas of humanities/business administration, biology/biomedicine, health and hard sciences. The occurrence of adventitious authors at this level of multidisciplinarity is uncommon in science. However, the possible benefits of such patterns are not clear in view of a fragmented intercommunication among the authors, as noticed through the citations. The advantages of changing this trend and of using other scientometric and bibliometric databases, such as SciELO, to avoid an almost exclusive use of the Web of Science database, are discussed.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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This research aims at verifying the authors who have given basis to the brazilian researches internationally inserted in the area of Bibliometrics and Scientometrics through the analysis of citation and co-citation of the brazilian articles published in the journal Scientometrics. We used the Scopus data base, with the terms Scientometrics in source title and Brasil or Brazil in affiliation country. We found 53 articles, with 741 references and 19 authors cited 3 or more times. In general, the researchers come from the biologic and health areas. Using the Ucinet software, we build the co-citation network and calculated its indicators. We calculated the co-citation normalized index. The density and average of normalized degree centrality were 65,5%. We concluded the research highlighting the significant presence of brazilians (32%) and the dialogicity occurring between cited Brazilians and foreigners within a balance, where brazilians already dialog with renowned international researchers of the Bibliometrics and Scientometrics area.

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El aprendizaje automático y la cienciometría son las disciplinas científicas que se tratan en esta tesis. El aprendizaje automático trata sobre la construcción y el estudio de algoritmos que puedan aprender a partir de datos, mientras que la cienciometría se ocupa principalmente del análisis de la ciencia desde una perspectiva cuantitativa. Hoy en día, los avances en el aprendizaje automático proporcionan las herramientas matemáticas y estadísticas para trabajar correctamente con la gran cantidad de datos cienciométricos almacenados en bases de datos bibliográficas. En este contexto, el uso de nuevos métodos de aprendizaje automático en aplicaciones de cienciometría es el foco de atención de esta tesis doctoral. Esta tesis propone nuevas contribuciones en el aprendizaje automático que podrían arrojar luz sobre el área de la cienciometría. Estas contribuciones están divididas en tres partes: Varios modelos supervisados (in)sensibles al coste son aprendidos para predecir el éxito científico de los artículos y los investigadores. Los modelos sensibles al coste no están interesados en maximizar la precisión de clasificación, sino en la minimización del coste total esperado derivado de los errores ocasionados. En este contexto, los editores de revistas científicas podrían disponer de una herramienta capaz de predecir el número de citas de un artículo en el fututo antes de ser publicado, mientras que los comités de promoción podrían predecir el incremento anual del índice h de los investigadores en los primeros años. Estos modelos predictivos podrían allanar el camino hacia nuevos sistemas de evaluación. Varios modelos gráficos probabilísticos son aprendidos para explotar y descubrir nuevas relaciones entre el gran número de índices bibliométricos existentes. En este contexto, la comunidad científica podría medir cómo algunos índices influyen en otros en términos probabilísticos y realizar propagación de la evidencia e inferencia abductiva para responder a preguntas bibliométricas. Además, la comunidad científica podría descubrir qué índices bibliométricos tienen mayor poder predictivo. Este es un problema de regresión multi-respuesta en el que el papel de cada variable, predictiva o respuesta, es desconocido de antemano. Los índices resultantes podrían ser muy útiles para la predicción, es decir, cuando se conocen sus valores, el conocimiento de cualquier valor no proporciona información sobre la predicción de otros índices bibliométricos. Un estudio bibliométrico sobre la investigación española en informática ha sido realizado bajo la cultura de publicar o morir. Este estudio se basa en una metodología de análisis de clusters que caracteriza la actividad en la investigación en términos de productividad, visibilidad, calidad, prestigio y colaboración internacional. Este estudio también analiza los efectos de la colaboración en la productividad y la visibilidad bajo diferentes circunstancias. ABSTRACT Machine learning and scientometrics are the scientific disciplines which are covered in this dissertation. Machine learning deals with the construction and study of algorithms that can learn from data, whereas scientometrics is mainly concerned with the analysis of science from a quantitative perspective. Nowadays, advances in machine learning provide the mathematical and statistical tools for properly working with the vast amount of scientometrics data stored in bibliographic databases. In this context, the use of novel machine learning methods in scientometrics applications is the focus of attention of this dissertation. This dissertation proposes new machine learning contributions which would shed light on the scientometrics area. These contributions are divided in three parts: Several supervised cost-(in)sensitive models are learned to predict the scientific success of articles and researchers. Cost-sensitive models are not interested in maximizing classification accuracy, but in minimizing the expected total cost of the error derived from mistakes in the classification process. In this context, publishers of scientific journals could have a tool capable of predicting the citation count of an article in the future before it is published, whereas promotion committees could predict the annual increase of the h-index of researchers within the first few years. These predictive models would pave the way for new assessment systems. Several probabilistic graphical models are learned to exploit and discover new relationships among the vast number of existing bibliometric indices. In this context, scientific community could measure how some indices influence others in probabilistic terms and perform evidence propagation and abduction inference for answering bibliometric questions. Also, scientific community could uncover which bibliometric indices have a higher predictive power. This is a multi-output regression problem where the role of each variable, predictive or response, is unknown beforehand. The resulting indices could be very useful for prediction purposes, that is, when their index values are known, knowledge of any index value provides no information on the prediction of other bibliometric indices. A scientometric study of the Spanish computer science research is performed under the publish-or-perish culture. This study is based on a cluster analysis methodology which characterizes the research activity in terms of productivity, visibility, quality, prestige and international collaboration. This study also analyzes the effects of collaboration on productivity and visibility under different circumstances.

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The thesis investigates the properties of two trends or time series which formed a:part of the Co-Citation bibliometric model "X~Ray Crystallography and Protein Determination in 1978, 1980 and 1982". This model was one of several created for the 1983 ABRC Science Policy Study which aimed to test the utility of bibliometric models in a national science policy context. The outcome of the validation part of that study proved to be especially favourable concerning the utility of trend data, which purport to model the development of speciality areas in science over time. This assessment could have important implications for the use of such data in policy formulation. However one possible problem with the Science Policy Study's conclusions was that insufficient time was available in the study for an in-depth analysis of the data. The thesis aims to continue the validation begun in the ABRC study by providing a detailed.examination of the characteristics of the data contained in the Trends numbered 11 and 44 in the model. A novel methodology for the analysis of the properties of the trends with respect to their literature content is presented. This is followed by an assessment based on questionnaire and interview data, of the ability of Trend 44 to realistically model the historical development of the field of mobile genetic elements research over time, with respect to its scientific content and the activities of its community of researchers. The results of these various analyses are then used to evaluate the strenghts and weaknesses of a trend or time series approach to the modelling of the activities of scientifiic fields. A critical evaluation of the origins of the discovered strengths and weaknesses.in the assumptions underlying the techniques used to generate trends from co-citation data is provided. Possible improvements. to the modelling techniques are discussed.

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Brazilian science has increased fast during the last decades. An example is the increasing in the country`s share in the world`s scientific publication within the main international databases. But what is the actual weight of international publications to the whole Brazilian productivity? In order to respond this question, we have elaborated a new indicator, the International Publication Ratio (IPR). The data source was Lattes Database, a database organized by one of the main Brazilian S&T funding agency, which encompasses publication data from 1997 to 2004 of about 51,000 Brazilian researchers. Influences of distinct parameters, such as sectors, fields, career age and gender, are analyzed. We hope the data presented may help S&T managers and other S&T interests to better understand the complexity under the concept scientific productivity, especially in peripheral countries in science, such as Brazil.

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Fractional calculus generalizes integer order derivatives and integrals. During the last half century a considerable progress took place in this scientific area. This paper addresses the evolution and establishes an assertive measure of the research development.

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Crabs of the genus Uca Leach, 1814 are characterized by having strong sexual dimorphism and a global distribution. Currently, 97 species have been described and analyzed under several aspects, including population ecology, physiology and ethology. However, there is no general summary of the information from the various literatures. The aim of this study is to perform a scientometric analysis of fiddler crab studies. For this we searched papers available in the Thomson ISI database that contained the words "Uca" OR "fiddler* crab*" between the years 1991 and 2007. For each paper, we researched and recorded the following characteristics: publication year; journal of publication; the first author's nationality; the country where the study was conducted; study type; species studied; and the work area. Our results indicated that there was no increase in the number of articles through the years considered. The Journal of Experimental Marine Biology and Ecology published most of the articles on Uca, indicating the importance of this group as a model for testing ecological hypotheses using experimental approaches. Our results also showed that United States had the highest number of authors and published studies on Uca, following the overall trend in dominance on scientific research. Furthermore, using models with three variables (per capita income, number of species of Uca and extent of coastal countries) we observed that, according to the Akaike Information Criterion, the per capita income was the most important correlate for the number of articles per country (both the author's country and country of study). Additionally, our results show that the species U. pugilator (distributed on the East Coast of the North American continent) was the species most singularly referenced in the papers considered. Moreover, our results indicate that most studies on Uca use a descriptive and local scale. The majority of papers in our literature search reflect studies in population biology, followed by behavioral and physiological characteristics.

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Records with the search string biogeograph* were collected from the Science Citation Index (SCI). A total of 3456 records were downloaded for the 1945-2006 period from titles of articles and reviews, and 10,543 records were downloaded for 1991-2006, taking into consideration also abstracts and keywords. Temporal trends of publications, geographical and institutional distribution of the research output, authorship, and core journals were evaluated. There were as many as 122 countries carrying out biogeographic research; in the most recent period, USA is the top producing country, followed by the United Kingdom, Australia, France, Germany, Spain, and Canada. There were 17,493 authors contributing to the field. During 1991-2006 there were 4098 organizations with authors involved in biogeographic research; institutions with higher number of papers are the Natural History Museum (United Kingdom), the University of California, Berkeley (USA), the Museum National d'Histoire Naturelle (France), the Universidad Nacional Autónoma de México (Mexico), the American Museum of Natural History (USA) and the Russian Academy of Sciences (Russia). Research articles are spread over a variety of journals, with the Journal of Biogeography, Molecular Phylogenetics and Evolution, Molecular Ecology, and Biological Journal of the Linnean Society being the core journals. From 28,759 keywords retrieved those with the highest frequency were evolution, phylogeny, diversity, mitochondrial DNA, pattern(s), systematics, and population(s). We conclude that publications on biogeography have increased substantially during the last years, especially since 1998. The preferred journal for biogeographic papers is the Journal of Biogeography. Most frequent keywords seem to indicate that biogeography fits well within both evolutionary biology and ecology, with molecular biology and phylogenetics being important factors that drive their current development.

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The objective of the present survey was to assess the Brazilian scientific production in psychiatry, psychobiology, and mental health during the 1998-2002 period. The universities' graduate programs concentrate the vast majority of the scientific production in Brazil. We assessed the annual reports from the graduate programs to the Brazilian Ministry of Education concerning master's and doctoral theses and the articles published in journals indexed by the Institute of Scientific Information (ISI). There are nine Master's and Doctoral graduate programs dedicated to research in psychiatry, neuropsychiatry, psychobiology, and mental health in the country, seven being located in southern states. During the 5-year period, from 1998 to 2002, 186 students received their doctorate degree (37/year). The programs published 637 articles in journals indexed by ISI, the majority of them in journals with an impact factor higher than 2. The research advisors' productivity varied among graduate programs, ranging from 0.6 to 2.0 articles per year in ISI-indexed journals. Despite the substantial barriers faced by the Brazilian scientific community (mainly financial and writing difficulties), Brazil's scientific mental health production is on the rise. The number of articles published in ISI-indexed journals has doubled without a significant increase in the number of graduate theses, suggesting that there was an improvement in both the quality of the scientific production and the productivity of the graduate programs. Based on these data, it is reasonable to predict a tendency to an increase in production over the next few years.

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Brazilian scientific output exhibited a 4-fold increase in the last two decades because of the stability of the investment in research and development activities and of changes in the policies of the main funding agencies. Most of this production is concentrated in public universities and research institutes located in the richest part of the country. Among all areas of knowledge, the most productive are Health and Biological Sciences. During the 1998-2002 period these areas presented heterogeneous growth ranging from 4.5% (Pharmacology) to 191% (Psychiatry), with a median growth rate of 47.2%. In order to identify and rank the 20 most prolific institutions in these areas, searches were made in three databases (DataCAPES, ISI and MEDLINE) which permitted the identification of 109,507 original articles produced by the 592 Graduate Programs in Health and Biological Sciences offered by 118 public universities and research institutes. The 20 most productive centers, ranked according to the total number of ISI-indexed articles published during the 1998-2003 period, produced 78.7% of the papers in these areas and are strongly concentrated in the Southern part of the country, mainly in São Paulo State.

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An analysis of scientific bibliographic productivity using the Hirsch h-index, information from the Institute of Scientific Information database and the Curriculum Lattes (CNPq, Brazil) was performed at the Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo (FFCLRP-USP) that has four departments in natural, biological and social sciences. Bibliometric evaluations of undergraduate programs showed a better performance of the departments of Chemistry (P < 0.001) and Biology (P < 0.001) when compared to the departments of Physics and Mathematics and Psychology and Education. We also analyzed the scientific output of the six graduate programs of FFCLRP: Psychology, Psychobiology, Chemistry, Physics Applied to Medicine and Biology, Comparative Biology, and Entomology. The graduate program in Psychology presented a lower h-index (P < 0.001) and had fewer papers indexed by the ISI web of science (P < 0.001) when compared to the other graduate programs. The poorer performance of the Psychology program may be associated with the limited coverage by the Thompson Institute of Scientific Information database.

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A new scientometric indicator, the h-index, has been recently proposed (Hirsch JE. Proc Natl Acad Sci 2005; 102: 16569-16572). The index avoids some shortcomings of the calculation of the total number of citations as a parameter to evaluate scientific performance. Although it has become known only recently, it has had widespread acceptance. A comparison of the average h-index of members of the Brazilian Academy of Sciences (BAS) and of the National Academy of Sciences of the USA (NAS-USA) was carried out for 10 different areas of science. Although, as expected, the comparison was unfavorable to the members of the BAS, the imbalance was distinct in different areas. Since these two academies represent, to a significant extent, the science of top quality produced in each country, the comparison allows the identification of the areas in Brazil that are closer to the international stakeholders of scientific excellence. The areas of Physics and Mathematics stand out in this context. The heterogeneity of the h-index in the different areas, estimated by the median dispersion of the index, is significantly higher in the BAS than in the NAS-USA. No elements have been collected in the present study to provide an explanation for this fact.

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A recent assessment of 4400 postgraduate courses in Brazil by CAPES (a federal government agency dedicated to the improvement of the quality of and research at the postgraduate level) stimulated a large amount of manifestations in the press, scientific journals and scientific congresses. This gigantic effort to classify 16,400 scientific journals in order to provide indicators for assessment proved to be puzzling and methodologically erroneous in terms of gauging the institutions from a metric point of view. A simple algorithm is proposed here to weigh the scientometric indicators that should be considered in the assessment of a scientific institution. I conclude here that the simple gauge of the total number of citations accounts for both the productivity of scientists and the impact of articles. The effort spent in this exercise is relatively small, and the sources of information are fully accessible. As an exercise to estimate the value of the methodology, 12 institutions of physics (10 from Brazil, one from the USA and one from Italy) have been evaluated.

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L’objectif de cette étude est de saisir une image des éléments explicitement reconnaissables de la recherche en communication visibles dans les revues savantes Canadian Journal of Communication et dans Communication de 1974 à 2005. Il s’agit d’une analyse bibliométrique des articles publiés par les chercheurs d’institutions canadiennes et de leurs références bibliographiques. La bibliométrie est « l’application de méthodes statistiques aux livres et aux autres moyens de communication » (Pritchard, 1969: 348-349). C’est la première fois qu’une analyse de ce type est tentée dans ce corpus particulier. Nous nous sommes appuyés sur des postulats théoriques provenant de la sociologie des sciences et des études en communication scientifique. L’idée maîtresse est la suivante : l’activité scientifique est un « continuum de création de nouvelles connaissances » (Vassallo, 1999), dont l’organisation est basée sur l’échange d’information (Price, 1963; Crane, 1972), qui se traduit en reconnaissance sociale, en autorité scientifique, et constitue un investissement pour l’acquisition de crédibilité (Merton, 1938; Hagstrom, 1965; Bourdieu, 1975; Latour et Woolgar, 1986). À partir de l’analyse des articles, nous identifions s’ils sont le résultat de recherches empiriques ou fondamentales, ou le produit d’une réflexion critique. Il s’agit aussi de détecter les approches méthodologiques et les techniques d’investigation utilisées, ainsi que les sujets qui y sont abordés par les chercheurs. Nous détectons également les principaux lieux de recherche (universités et types de départements). Nous analysons aussi les thématiques des articles. Enfin, nous analysons des références bibliographiques des articles afin de cerner les sources d’idées qui y sont décelables. Notre corpus principal comporte 1154 articles et 12 840 titres de documents en référence. L’analyse bibliométrique des articles révèle ainsi une recherche canadienne en communication d’emblée qualitative, intéressée pour les spécificités historiques, le contexte social et la compréhension des interrelations sous-jacentes aux phénomènes de communication, en particulier, au Canada et au Québec. Au cœur de ces études se distingue principalement l’application de l’analyse de contenu qualitative dans les médias en général. Cependant, à partir de 1980, l’exploration du cinéma, de l’audiovisuel, des nouvelles technologies de l’information et de la communication, ainsi que la multiplication des sujets de recherche, annoncent un déplacement dans l’ordre des intérêts. Communication et le CJC, se distinguent cependant par l’origine linguistique des chercheurs qui y publient ainsi que dans les thématiques. L’analyse des références bibliographiques, et de leurs auteurs, met en relief l’intérêt partagé des chercheurs d’institutions universitaires canadiennes pour les agences de réglementation et les politiques gouvernementales canadiennes s’appuyant souvent sur l’analyse de documents législatifs et de rapports de diverses commissions d’enquête du gouvernement canadien. L’analyse révèle aussi les principales inspirations théoriques et méthodologiques des chercheurs. Parmi les plus citées, on voit Innis, McLuhan, Habermas, Tuchman, Bourdieu, Foucault, Raboy, et Rogers. Mais ces références évoluent dans le temps. On voit aussi une distinction relativement claire entre les sources citées par la recherche francophone et la recherche anglophone.