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1.
PLoS One ; 11(5): e0155732, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27195701

RESUMO

Assessing the research of individual scholars is currently a matter of serious concern and worldwide debate. In order to gauge the long-term efficacy and efficiency of this practice, we carried out a limited survey of the operation and outcome of Mexico's 30-year old National System of Investigators or SNI, the country's main instrument for stimulating competitive research in science and technology. A statistical random sample of researchers listed in the area of Humanities and Behavioral Sciences-one of SNI's first and better consolidated academic divisions comprising a wide range of research disciplines, from philosophy to pedagogy to archaeology to experimental brain research-was screened comparing individual ranks or "Levels of distinction" to actual compliance with the SNI's own evaluation criteria, as reflected in major public databases of scholarly production. The same analysis was applied to members of a recent Review Committee, integrated by top-level researchers belonging to that general area of knowledge, who have been in charge of assessing and ranking their colleagues. Our results for both sets of scholars show wide disparity of individual productivity within the same SNI Level, according to all key indicators officially required (books issued by prestigious publishers, research articles appeared in indexed journals, and formation of new scientists), as well as in impact estimated by numbers of citations. Statistical calculation from the data indicates that 36% of members in the Review Committee and 53% of researchers in the random sample do not satisfy the official criteria requested for their appointed SNI Levels. The findings are discussed in terms of possible methodological errors in our study, of relevance for the SNI at large in relation to independent appraisals, of the cost-benefit balance of the organization as a research policy tool, and of possible alternatives for its thorough restructuring. As it currently stands SNI is not a model for efficient and effectual national systems of research assessment.


Assuntos
Ciências do Comportamento/estatística & dados numéricos , Ciências Humanas/estatística & dados numéricos , Editoração/estatística & dados numéricos , Pesquisa , Comitês Consultivos , Bibliometria , Bases de Dados Factuais , Humanos , Conhecimento , México , Método de Monte Carlo , Reprodutibilidade dos Testes , Pesquisadores/estatística & dados numéricos
2.
PLoS One ; 9(5): e93949, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24817403

RESUMO

The number of scholarly documents available on the web is estimated using capture/recapture methods by studying the coverage of two major academic search engines: Google Scholar and Microsoft Academic Search. Our estimates show that at least 114 million English-language scholarly documents are accessible on the web, of which Google Scholar has nearly 100 million. Of these, we estimate that at least 27 million (24%) are freely available since they do not require a subscription or payment of any kind. In addition, at a finer scale, we also estimate the number of scholarly documents on the web for fifteen fields: Agricultural Science, Arts and Humanities, Biology, Chemistry, Computer Science, Economics and Business, Engineering, Environmental Sciences, Geosciences, Material Science, Mathematics, Medicine, Physics, Social Sciences, and Multidisciplinary, as defined by Microsoft Academic Search. In addition, we show that among these fields the percentage of documents defined as freely available varies significantly, i.e., from 12 to 50%.


Assuntos
Disseminação de Informação , Internet/estatística & dados numéricos , Publicações/estatística & dados numéricos , Ferramenta de Busca/estatística & dados numéricos , Economia/estatística & dados numéricos , Ciências Humanas/estatística & dados numéricos , Humanos , Medicina/estatística & dados numéricos , Física/estatística & dados numéricos , Ciência/estatística & dados numéricos
3.
PLoS One ; 4(3): e4803, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19277205

RESUMO

BACKGROUND: Intricate maps of science have been created from citation data to visualize the structure of scientific activity. However, most scientific publications are now accessed online. Scholarly web portals record detailed log data at a scale that exceeds the number of all existing citations combined. Such log data is recorded immediately upon publication and keeps track of the sequences of user requests (clickstreams) that are issued by a variety of users across many different domains. Given these advantages of log datasets over citation data, we investigate whether they can produce high-resolution, more current maps of science. METHODOLOGY: Over the course of 2007 and 2008, we collected nearly 1 billion user interactions recorded by the scholarly web portals of some of the most significant publishers, aggregators and institutional consortia. The resulting reference data set covers a significant part of world-wide use of scholarly web portals in 2006, and provides a balanced coverage of the humanities, social sciences, and natural sciences. A journal clickstream model, i.e. a first-order Markov chain, was extracted from the sequences of user interactions in the logs. The clickstream model was validated by comparing it to the Getty Research Institute's Architecture and Art Thesaurus. The resulting model was visualized as a journal network that outlines the relationships between various scientific domains and clarifies the connection of the social sciences and humanities to the natural sciences. CONCLUSIONS: Maps of science resulting from large-scale clickstream data provide a detailed, contemporary view of scientific activity and correct the underrepresentation of the social sciences and humanities that is commonly found in citation data.


Assuntos
Bibliometria , Pesquisa/estatística & dados numéricos , Algoritmos , Bases de Dados Bibliográficas/estatística & dados numéricos , Ciências Humanas/estatística & dados numéricos , Cadeias de Markov , Modelos Teóricos , Disciplinas das Ciências Naturais/estatística & dados numéricos , Sistemas On-Line , Publicações Periódicas como Assunto/estatística & dados numéricos , Ciências Sociais/estatística & dados numéricos
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