Search Results

You are looking at 11 - 20 of 22 items for :

  • Mathematics and Statistics x
  • Refine by Access: All Content x
Clear All

Summary  

The rhythm of science may be compared to the rhythm of music. The R-indicator studied in this article is a complex indicator, trying to reflect part of this rhythm. The R-indicator interweaves publication and citation data over a long period. In this way R-sequences can be used to describe the evolutionary rhythm of science considered in a novel way. As an example the R-sequence of the journal Science from 1945 on is calculated.

Restricted access

Abstract  

Studying three Chinese major universities of different type, this article attempts to validate earlier results related to authors' name order in papers co-authored by graduate candidates and their supervisors. Candidates for the doctoral degree as well as the master's degree are considered. Defining the g-ratio as the fraction of co-authored publications where the graduate student's name precedes that of the supervisor's we obtain the following results. 1) Generally, master's level g-ratios are smaller than the corresponding doctoral level g-ratios. 2) The three doctoral g-ratio time series have a common characteristic: they tend to a limiting target value of somewhat more than 80%. The master's time series of the three universities extend themselves in parallel with the doctoral time series. 3) The g-ratio of collaborative papers related to the dissertation is higher than the g-ratio of collaborative papers not related to the dissertation. This is true on the doctoral level as well as on the master's level. 4) Different disciplines have different g-ratios, representing disciplinary customs in graduate candidate-supervisor collaboration, the highest g-ratio in the doctoral case occurring in biology (except for Tsinghua University that does not offer courses in biology). 5) There exist only small differences between the g-ratios of different kinds of universities. 6) In recent years, the same candidate-supervisor collaboration patterns exist in international publications as in domestic ones. The fact that the doctoral g-ratios of all three universities are as high as 80% reflects a universal regularity in the structure of scientific collaboration between doctoral candidates and their supervisors in China.

Restricted access

Abstract  

The objective of this study is to use a clustering algorithm based on journal cross-citation to validate and to improve the journal-based subject classification schemes. The cognitive structure based on the clustering is visualized by the journal cross-citation network and three kinds of representative journals in each cluster among the communication network have been detected and analyzed. As an existing reference system the 15-field subject classification by Glänzel and Schubert (Scientometrics 56:55–73, <cite>2003</cite>) has been compared with the clustering structure.

Restricted access

Summary  

To compare science growth of different countries is both, of theoretical and of pragmatic interest. Using methods for the analysis of complex growth processes introduced by H. E. Stanley and others, we exhibit quantitative features of Chinese science growth from 1986 to 1999 and compare them with corresponding features of western countries. Patterns of growth dynamics of Chinese universities publication output do not differ significantly from those found in the case of western countries. The same is valid for Chinese journals when compared to international journals. In nearly all cases the size distribution of output over universities or journals is near to a lognormal one, the growth rate distribution is Laplace-like, and the standard deviations of the corresponding conditional distributions with regard to size decay according to a power law. This means that regarding some structural-dynamical properties China's recent science system cannot be distinguished from a western one - despite different prehistory and different political and economic environment.

Restricted access
Scientometrics
Authors: Liming Liang, Hildrun Kretschmer, Yongzheng Guo, and Donald deB. Beaver

Abstract  

This paper is a scientometric study of the age structure of scientific collaboration in Chinese computer science. Analysis reveals some special age structures in scientific collaboration in Chinese computer science. Most collaborations are composed of scientists younger than thirty-six (Younger) or older than fifty (Elder). For two-dimensional collaboration formed by first and second authors, Younger-Elder and Younger-Younger are the predominant age structures. For three-dimensional collaboration formed by first, second and third authors, Younger-Younger-Elder and Younger-Younger-Younger are the most important age structures. Collaboration between two authors older than 38 amounts to only 6.4 percent of all two-person collaborations. Collaboration between two middle-aged scientists is seldom seen. Why do such types of age structure in Chinese computer science exist? We suggest a tentative explanation based on analyses of the age composition of all authors, the age distributions of the authors in different ranks, and the name-ordering of authors in articles written by professors and their students.

Restricted access

Abstract  

A statistical analysis is made of two data sets and it is found that the distribution of major scientific and technological achievements in terms of the age of those achievement makers is Weibull distribution. Pearson'sx 2 test results are satisfactory. This finding holds for different centuries, different nations and different disciplines.

Restricted access

Darstellung des iterierten Maßintegrals als Limes von iterierten Zwischensummen, I Journal f. d. reine und angew. Math. 237 181 – 193 10.1515/crll.1969

Restricted access

and spaces of mappings Comm. Math. Univ. Car. 6 257 – 278 . [28] Keller , H. 1968 Die Limes

Restricted access

] Keller , H. 1968 Die Limes-uniformisierbarkeit der Limesräume Math. Ann. 176 334 – 341 10.1007/BF02052894 . [22

Restricted access

organizers. The lime square and red circle nodes represent followers and members, respectively. The size of the node relates to the number of replies and retweets. Fig. 3 Two-mode network visualization by group

Restricted access