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Abstract  

The paper points out that the characteristic properties of general social networks are reflected in co-authorship patterns of theoretical population genetics as studied from 1900 to 1980. The results are consistent with the analyses of bibliographies where the co-authorship networks in invisible colleges probably have shown the same behavioural patterns as the non-scientific populations. The patterns of behaviour are portrayed in two-dimensional as well as three-dimensional representations of co-authorship data in theoretical population genetics.

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Abstract  

Studies of journal citation patterns suggest that specialty areas within disciplines may be the most appro priate structural units for understanding the social organization of science. Citation studies necessarily are limited to scientists who publish, however, and studies of all members of particular disciplines would provide more general specialty structure data. Accordingly, this research applied factor analytic procedures previously used in studies of the structure of specialization among psychologists to all members of the Population Association of America. Four principal components derived from the self-designated specialties of these population scientist were rotated to a final solution by the varimax procedure and were interpreted as measuring, respectively,Social Emphasis, Geographic Emphasis, Formal Emphasis, andEpidemiological Emphasis. These results partially confirm the distinction sometimes made by population scientists between social demography and formal demography, but suggest this typology is incomplete. The results also illustrate techniques that could provide a useful alternative to citation analysis for researchers studying specialty structures in other disciplines.

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Abstract  

Traces the growth of collaborated and funded research as reflected in research papers in theoretical population genetics research speciality from 1916–80 through a case study. Analyses the proportion and extent of collaborated papers, averge number of authorship per paper, and collaborative coefficient index of research papers thereby giving an overall perspective of the growth of professionalism in the field. Studies the relation between collaboration, productivity, and funding of research papers in theoretical population genetics. Classifies the total collaborative papers/authors by type of collaboration and studies the trends and shifts in the nature and type of collaborative research over the years.

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Abstract  

Analyses the growth of funded and collaborative research publications and authors as reflected in selected theoretical population genetics literature from 1956–60 to 1976–80. Indicates that the number of funded and collaborated publications has not proportionally increased along with the growth of total research publications and authors with time, but however, there is a strong correlation between the two. Indicates the extent of multi-authored research publications in different countries, and studies the growth of multi-authored publications from 1956–60 to 1976–80. Studies the impact of funding and collaboration on the productivity of authors over a period of time. Concludes that the authors who are more productive are generally found to be more collaborative and funded. The average productivity per author is observed to be larger in funded and collaborated authors subset and smaller in non-funded and non-collaborated authors subset, than the average productivity per author in the total authors subset in all the five block years studied. There is a systematic increase with time in the average productivity per author in the funded and collaborated authors subset. Studies the nature and type of collaborated research from 1956–60 to 1976–80, and the role of funding. Highlights the research priorities of few important countries in collabortive research. Indicates the collaboration linkages among various countries in transnational collaborative research. Concludes that with time, the focus of research is slowly shifting from internal collaration to domestic and international collaboration, supported by increasing funding from government agencies in theoretical population genetics research.

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Scientometrics
Authors: Juan Carlos Anduckia, Julián Gómez, and Yuri Jack Gómez

. Ausubel , H. 1996 Human population dynamics revisited with the logistic model: how much can be modelled and predicted? Technological Forecasting and Social Change 52 1

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Abstract  

This paper is a review of recent developments of a research line proposed on the turn of the decades, 1980s to 1990s. The main results concern basic qualitative properties of nonlinear models of population biology, such as controllability and observability. The methods applied are different for the density-dependent models of population ecology and for the frequency-dependent models of population genetics and evolutionary theory. While in the first case the classical theorems of nonlinear systems theory can be used, in the second one an extension of classical results to systems with invariant manifold is necessary.

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Abstract  

Studies the relation between growth rates and obsolescence rates and half-life of theoretical population genetics literature. Explores the application of lognormal distribution in age distribution of citations over a period of time.

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Abstract  

Focuses on the validity of Lotka's law and the negative binomial distribution model to author productivity data in different time periods in theoretical population genetics speciality. Finds out if there is any relation between applicability of a statistical distribution and the development of speciality. Looks at the linkages between inequality/concentration measures and the development of speciality. Explores the relevance and applicability of the two generalisations, namely Price Square, Root Law and 80/20 Rule to the author productivity data and their relation with development of theoretical population genetics. Finally, a study of the growth of practitioners in the field with different productivity levels is conducted, and the emergence of core authors in the speciality is explored.

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Abstract  

The study analyses the distribution of productivity of authors in theoretical population genetics (TPG) as reflected in their publication output from 1881 to 1980 from two different approaches. The internal dynamics of TPG specialty affecting the distribution of the productivity of authors is studied using time cross-sectional type of approach. Here the productivity distribution of authors in 10 time-year blocks and in three phases of the development (1921-50, 1951-65 and 1966-80) of TPG is studied using cohort type of approach. The extent of cumulative advantage acquired by the prolific group of authors over time in TPG is also studied. The paper also analyzes the regularity in the distribution of productivity of various cohorts, having same length of activity, but different periods of participation.

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Scientometrics
Authors: Luís Bettencourt, David Kaiser, Jasleen Kaur, Carlos Castillo-Chávez, and David Wojick

Abstract  

We analyze the temporal evolution of emerging fields within several scientific disciplines in terms of numbers of authors and publications. From bibliographic searches we construct databases of authors, papers, and their dates of publication. We show that the temporal development of each field, while different in detail, is well described by population contagion models, suitably adapted from epidemiology to reflect the dynamics of scientific interaction. Dynamical parameters are estimated and discussed to reflect fundamental characteristics of the field, such as time of apprenticeship and recruitment rate. We also show that fields are characterized by simple scaling laws relating numbers of new publications to new authors, with exponents that reflect increasing or decreasing returns in scientific productivity.

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