Studies in Scientometrics I Transience and Continuance in Scientific Authorship

Estuda o fenomeno de transiencia/permanencia na frente de pesquisa pela analise do fluxo anual de autores de uma populacao amostrada derivada do banco de dados resultante de sete anos de publicacao de "Science Citation Index" e "Who is publishing in Science". Para o periodo total analisado (1964-1970) foram encontrados 281 autores transientes e 19 autores permanentes, numa populacao total de 506 autores. Derivou-se, a seguir, um modelo para analise quantitativa do fluxo padrao de autores, verificando-se que ha uma taxa de natalidade ("annual recruitment") e uma taxa de mortalidade ("annual terminatio") de cuja superposicao resulta uma taxa de mortalidade infantil (transiencia). O modelo final permite definir a existencia de um nucleo de autores altamente permanentes, correspondente a 20% da populacao. Os autores transientes constituem 22% da populacao anual e 2/3 dos autores novos ("newcomers"). Foram ainda identificadas outras categorias de autores na comunidade cientifica. Ha uma clara correlacao entre estas propriedades demograficas e as taxas (maior e menor) de produtividade dos autores, cuja distribuicao e consistente com as leis de Lotka e Price. Isto permite derivar a expectativa de permanencia na frente de pesquisa, que sera proporcional ao tempo ativo de publicacao. Temos de um lado da escala, a maioria dos autores com uma expectativa de vida minima e taxa de produtividade baixa (75% dos autores produzindo 25% dos trabalhos); no lado oposto estao os autores do nucleo permanente (20%), com menor taxa de mortalidade e maior taxa de produtividade (mais que a metade dos trabalhos). Esta situacao e resultante de um feedback positivo ou efeito Matthew — e parece ser tao intrinseca que, tudo leva a crer, nossa sociedade deve atingir de modo a adaptar sua estrutura institucional a feicao da produtividade e demografia cientificas. 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.