87 research outputs found

    Life, Death and Preferential Attachment

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    Scientific communities are characterized by strong stratification. The highly skewed frequency distribution of citations of published scientific papers suggests a relatively small number of active, cited papers embedded in a sea of inactive and uncited papers. We propose an analytically soluble model which allows for the death of nodes. This model provides an excellent description of the citation distributions for live and dead papers in the SPIRES database. Further, this model suggests a novel and general mechanism for the generation of power law distributions in networks whenever the fraction of active nodes is small.Comment: 5 pages, 2 figure

    Society's needs in scientific and technical information

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    Processa-se, presentemente, uma segunda revolução na transmissão da informação científica, comparável, talvez, ao advento do periódico científico. A rapidez de comunicação na frente de pesquisa não mais depende do sistema de comunicação da literatura periódica, que permanece, no entanto, o principal veículo para o registro do conhecimento científico. Um sistema moderno poderia incluir um periódico diário, para rápida disseminação, e também um conjunto de periódicos baseado em uma coleção de documentos reestruturado em classes, de acordo com correlação de citações. Desta forma, os processos de utilização, e validade seriam separados dos cie acumulação do registro científico, em vez de combinados, como acontece no presente sistema. As técnicas bibliométricas atuais tornam tal estrutura possível. Abstract A second revolution in the transmission of scientific information, perhaps comparable to the advent of the scientific journal is presently underway. Rapid research front communication is no longer dependent upon the journal communication system which remains, however, the key record of the accumulation of scientific knowledge. A modern system might well include a daily newspaper format for high speed dissemination and a restructured set of journals based on the collection of papers into classes on the basis of their citation linkages. The processes of use and validation would thus be separated from that of the cumulation of scientific record, rather than combined as in the present system. Current bibliometric techniques make such a structure possible

    Studies in Scientometrics I Transience and Continuance in Scientific Authorship

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    Estuda o fenômeno de transiência/permanência na frente de pesquisa pela análise do fluxo anual de autores de uma população amostrada derivada do banco de dados resultante de sete anos de publicação de "Science Citation Index" e "Who is publishing in Science". Para o período total analisado (1964-1970) foram encontrados 281 autores transientes e 19 autores permanentes, numa população total de 506 autores. Derivou-se, a seguir, um modelo para análise quantitativa do fluxo padrão de autores, verificando-se que há uma taxa de natalidade ("annual recruitment") e uma taxa de mortalidade ("annual terminatio") de cuja superposição resulta uma taxa de mortalidade infantil (transiência). O modelo final permite definir a existência de um núcleo de autores altamente permanentes, correspondente a 20% da população. Os autores transientes constituem 22% da população anual e 2/3 dos autores novos ("newcomers"). Foram ainda identificadas outras categorias de autores na comunidade científica. Há uma clara correlação entre estas propriedades demográficas e as taxas (maior e menor) de produtividade dos autores, cuja distribuição é consistente com as leis de Lotka e Price. Isto permite derivar a expectativa de permanência na frente de pesquisa, que será proporcional ao tempo ativo de publicação. Temos de um lado da escala, a maioria dos autores com uma expectativa de vida mínima e taxa de produtividade baixa (75% dos autores produzindo 25% dos trabalhos); no lado oposto estão os autores do núcleo permanente (20%), com menor taxa de mortalidade e maior taxa de produtividade (mais que a metade dos trabalhos). Esta situação é resultante de um feedback positivo ou efeito Matthew — e parece ser tão intrínseca que, tudo leva a crer, nossa sociedade deve atingir de modo a adaptar sua estrutura institucional à feição da produtividade e demografia científicas. Abstract Investigation of the transience / continuance phenomenon occurring at a research front. The annual output of authors in a random sample derived from seven years data from Science Citation Index and Who is publishing in Science was analysed. In the whole period (1964-1970) there are 281 transient authors and 19 continuant authors, for a total population of 506 authors. By deriving a quantitative model for the author flow pattern analysis, it was shown that there is a birth rate (annual recruitment) and a death rate (annual termination) which overlap to give an infant mortality (transience). By refining the model, it was possible to define a core of continuant authors, which amounts to 20% of those publishing. The transient authors constitute 22% of the annual population and 2/3 of the newcomers to publication. The other identified components of a scientific community are the recruits, terminators, non-core publishing continuants and non-publishing continuants. These demographic properties are clearly associated with the lowest and highest rates of  authors' productivity, the distributions of which folkw Lotka's and Price's laws with great regularity. Thus it was possible to derive a lifetime expectancy at the research front which will be proportional to the time of active publication. On one end of the scale there is a majority of authors with a minimum life expectancy and a low average productivity (75% of the authors produce 25% of the papers); at the opposite extreme there are authors in the permanent nucleus (20%) with less average mortality and greater average productivity (more than half of the papers) All this is a result of the positive feedback or Mathew Principle in scientific publication. This situation seems so intrinsic that it must be regarded at the way in which society has adjusted its institutional structure to fit the cloth of scientific productivity and demography

    Studies in scientometrics II. The relation between source author and cited author populations

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    Uma sequência anual de Citation Indexes mantém um padrão de comportamento em muito semelhante a uma sequência de Source Indexes. Cinco anos do Source Index (1964-1968) foram considerados como suficientes para distinguir, entre os autores, as classes de transientes e permanentes, e três anos do Citation Index (1966-1968) para identificar referências a autores iniciando publicação no começo do período. O arquivo listou 640 autores, dos quais 381 estavam incluídos nos cinco Source Indexes e 442 nos três Citation Indexes, sendo 183 nomes comuns a ambas categorias de índices. Dos autores transientes que aparecem apenas em um único Source Index, 71% não são citados, 19% são transitoriamente citados e somente 10% parecem ser permanentes em citação.Um autor transiente tem cerca de 30% de chance de ser citado em qualquer ano. Do núcleo de 22 autores permanentes que publicam nos cinco anos registrados,19 são também citados em todos os três anos. É importante notar que esses mesmos 19 autores são também aqueles que continuam não apenas por um períodode 5 anos mas pelo período de 7 anos registrados noestudo anterior. Os autores permanentes do Sourcetendem a ser permanentes também em citação. Um grupo de 259 autores que são citados não aparece entre os autores-fonte. Desses, 80% são transientes e 20%são permanentes. Com a edição de novos dados de citação e de características de grupos de autores não incluídos no Source, os grupos demográficos são distribuídos nas seguintes categorias: a) transientes, b) permanentes que não fazem parte do núcleo, c) permanentes integrantes ao núcleo, d) permanentes que continuam a ser citados embora não mais publiquem,e) antigos transientes e f) novos permanentes. Abstract A sequence of annual Citation Indexes behaves in very much the same way as the sequence of Source Indexes. Five years o f Source Index were regarded (1964-1968) as sufficient to distinguish the transient and continuant classes amongst the authors,and three years o f the Citation Index (1966-1968) to pick up references to authors commencing publication at the begining of the period. The file listed 640 authors of which 381 were in the five Source Indexes and 442 in the three Citation Indexes with 183 names being common to both sets of index.O f the transient authors who appear in only a single Source Index 71% are uncited, 19% are transiently cited and only 10% seem to be continuants in citation. A transient author has about 30% chance of being cited in any year. Of the core continuant authors who publish in ali five years of record, 19 of the 22 are also cited in all the three years. It's worth noting that these 19 authors are also those who continue not merely for a five year span but for the seven years recorded in the previous study. Continuant source authors have astrong tendency to be continuants also in citation.A considerable group of 259 names in Citation Index do not appear amongst the source authors. Of the 259 names 80% are transiently cited and 20% are continuants. With the addition of new citation data and the characteristics oft he non-sourcegroups, not before detected, the demographic groups now become as: a) transients b) non-core continuants c) core continuants d) terminated continuants e) former transients f) newly recruited continuants

    Is Inequality Among Universities Increasing? Gini Coefficients and the Elusive Rise of Elite Universities

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    One of the unintended consequences of the New Public Management (NPM) in universities is often feared to be a division between elite institutions focused on research and large institutions with teaching missions. However, institutional isomorphisms provide counter-incentives. For example, university rankings focus on certain output parameters such as publications, but not on others (e.g., patents). In this study, we apply Gini coefficients to university rankings in order to assess whether universities are becoming more unequal, at the level of both the world and individual nations. Our results do not support the thesis that universities are becoming more unequal. If anything, we predominantly find homogenization, both at the level of the global comparisons and nationally. In a more restricted dataset (using only publications in the natural and life sciences), we find increasing inequality for those countries, which used NPM during the 1990s, but not during the 2000s. Our findings suggest that increased output steering from the policy side leads to a global conformation to performance standards

    Hidden in the Middle : Culture, Value and Reward in Bioinformatics

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    Bioinformatics - the so-called shotgun marriage between biology and computer science - is an interdiscipline. Despite interdisciplinarity being seen as a virtue, for having the capacity to solve complex problems and foster innovation, it has the potential to place projects and people in anomalous categories. For example, valorised 'outputs' in academia are often defined and rewarded by discipline. Bioinformatics, as an interdisciplinary bricolage, incorporates experts from various disciplinary cultures with their own distinct ways of working. Perceived problems of interdisciplinarity include difficulties of making explicit knowledge that is practical, theoretical, or cognitive. But successful interdisciplinary research also depends on an understanding of disciplinary cultures and value systems, often only tacitly understood by members of the communities in question. In bioinformatics, the 'parent' disciplines have different value systems; for example, what is considered worthwhile research by computer scientists can be thought of as trivial by biologists, and vice versa. This paper concentrates on the problems of reward and recognition described by scientists working in academic bioinformatics in the United Kingdom. We highlight problems that are a consequence of its cross-cultural make-up, recognising that the mismatches in knowledge in this borderland take place not just at the level of the practical, theoretical, or epistemological, but also at the cultural level too. The trend in big, interdisciplinary science is towards multiple authors on a single paper; in bioinformatics this has created hybrid or fractional scientists who find they are being positioned not just in-between established disciplines but also in-between as middle authors or, worse still, left off papers altogether

    Happiness is a warm librarian

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    I want to emphasize the likelihood of enormous change in the course of adapting to the new technologies. These technologies will give rise to quite a new and essentially human need from librarians and information scientists, particularly for the gift of the peculiarly human pattern of thinking. In this little discourse I would like to set forth views which are those of a person who is only a hobbyist of information science... trying to balance the internal and external patterns of development of science and technology.published or submitted for publicatio

    Kis tudomány, nagy tudomány

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