Bibliometric features of some scientific subfields and the scientometric consequences therefrom

In the present work an attempt is made to select journal bases for some subfields in chemistry. Through the modification of the Hirst's discioline impact factor concept, theprimary information base for the selected subfields is detenained. Relating impact factors of citing and cited journals,citation strategy indicators are suggested. Determination of the mean impact factors for subfields enables the introduction ofsubfields factors that bring the impact factors of journals of various subfields on a comparavle level.     

Bibliometric analysis of publications of Spanish pharmacologists in the SCI (1984–89). Part II

During the period 1984–89 Spanish pharmacologists published 344 papers (44.3% of their total scientific production) (Science Citation Index, CD-Edition) in journals classified by theSCI in subfields different from Pharmacology & Pharmacy. Distribution by institutions, geographical regions, journals, subfields and research levels are presented. The Normalized Journal Position (NJP) is introduced as indicator of the expected impact in each subfield. Results are compared with those of the analysis of the production of Spanish pharmacologists in the Pharmacology & Pharmacy subfield, presented in a previous paper. Some of the features detected are common to both areas, such as: increasing trend in the productivity over years, irregular geographical distribution with three regions as major producers, or university as main producer institution. Special features of the extra-Pharmacology area are also pointed out: irregular growth of publication number over years, high dispersion of publications in journals and subfields, high collaboration rate, and low percentage of authors with at least 1 paper/year, among others. Attending to journal of publication, cross-disciplinarity research of Spanish pharmacologists is analysed, being Neurosciences, Biochemistry & Molecular Biology and Physiology, the main border fields involved.     

Spanish performance in life sciences. A comparative appraisal of the scientific production of Spain and five other European countries in 1989

The output in life science disciplines from Spain and five other European countries has been measured in a datafile derived from theCurrent Contents-Life Sciences on diskette (1989). The results of this flash evaluation were contrasted with data retrieved from a survey covering the yearly output during the 1973–83 period and thee 1981–85 aggregated value from Schubert, Glänzel, Braun datafiles. The results of these studies showed an increasing share of Spain in the six countries' output, especially in the subfields of organic chemistry and phytochemistry. However, the quality of the Spanish articles—as deduced from the journal impact factors (JRC-1989)—is below the six countries average. The usefulness of the Current Contents on diskette for handy and reliable flash evaluations has been ascertained through a comparative analysis with more comprehensive surveys.     

Subfield problems in applying the Garfield (Impact) Factors in practice

The assessment of the publications of research teams working on different subfields raises concerns because of the different scientometric features of the subfields. For equalizing the differences in the Garfield (Impact) Factors of journals, several methods applied in practice have been described. A new indicator – Specific Impact Contribution (SIC) relating the citation share of a respective team (or journal) in the total citations of the teams (or journals) evaluated to its share in publications – was introduced. It has been realized that the normalized Garfield Factors and the normalized SIC values are identical measures within any selected set of journals. Consequently, the Garfield Factor of a journal should be assumed as an indicator characterizing the contribution of the information channel as a whole, appropriately. This revised version was published online in June 2006 with corrections to the Cover Date.     

An indicator of cross-disciplinary research

Study of interdisciplinary research processes and performance is hampered by a lack of data. This project investigated possible indicators based in the open scientific literature to measure such processes. Focusing on theJournal Citation Reports as a suitable data base, alternative indicators were validated on a sample of 383 articles drawn from 19 journals. The results support the use ofCitations Outside Category as an indicator of cross-disciplinary research activity. An estimated version of this indicator is used to examine three research categories — Demography, Operations Research/Management Science, and Toxicology — as to the extent of cross-disciplinary citation occurring by the journals in these categories and to them. Results suggest thatCitations Outside Category can be a quite informative bibliometric measure. A key substantive finding is that citation across broad field categories (engineering, life sciences, physical sciences, and social sciences) is extremely infrequent.     

Cross-national assessment of specialization patterns in chemistry

In this study, the specialization profiles of eleven countries are compared along two interconnected but distinct dimensions of research, viz. publication output and citation impact in nine subfields of chemistry. The data for comparative analysis were taken from Scientometric Datafiles.¹Since raw counts of publications and citations are confounded by the size of the countries and the size of subject fields, cross-national comparison is made, using relative indicators—activity index and attractivity index. The subfields of relative strength and weakness for these countries are identified from the values of these indicators. The similarity structure of specialization profiles of the eleven countries is mapped, using hierarchical cluster analysis and multidimensional scaling. This mapping leads to the representation of chemistry as it is structured by the dynamics of national science policies of these countries.     

Non-English journals and papers in physics and chemistry: bias in citations?

This study investigates, at the journal as well as the article level, if there is a difference in citations between English-language and non-English publications. The Web of Knowledge is used as data source. The investigation focuses on the fields of physics and chemistry. Using a precise definition of a “non-English journal”, we filter out nine physics and thirty-four chemistry non-English journals, scattered over six physics and seven chemistry subfields. Average received citations per paper (CpP) of the non-English journal(s) are compared with the CpP of pure English journals, and this in the same subfield. We clearly observe that non-English journals are inferior—in number of citations received—to pure English journals and this in all physics and chemistry subfields studied. Further, twelve physics journals and ten chemistry journals were chosen as sample journals to compare the CpP of non-English papers with that of English language papers in the same journal. The result of this comparison is that for the majority of these journals and for most of the publication years the CpP of non-English papers is lower than that of the English language papers. Finally, analyzing linguistic characteristics of the citing literature confirms the own-language preference in non-English physics and chemistry journals.     

Science publication indicators for India: Questions of interpretation

We comment on a letter toNature in 1996 on the long term decline of Indian science pointing out methodological reasons why the (SCI) data used by the authors do not unambiguously lead to their stated conclusions. Our arguments are based on the contention that no valid statement on change in a country's output may be made for a period in which the journal coverage from that country in SCI has changed significantly. We have suggested that for longitudinal comparisons of country level performance, it should be verified that the journals from that country in SCI remained constant within the period. This could be ensured if the country of publication of journals could be included as a field in the SCI database. We define a Visibility Index as the cumulated impact and derive a relation to estimate change in visibility combining changes in output and average impact. In the period during which Indian journal coverage remained unchanged, a detailed analysis of output for two years (1990–94) leads us to conclude that, with the exception of Agriculture, there has been an increase in publication in virtually every field, with significant increase in the overall mean Impact Factor. At least 25 subfields have been identified with statistically significant increase in mean Impact Factor and Visibility. The impact of foreign collaboration on visibility has also been considered. In conclusion we touch upon the question of citation as a performance indicator for Third World countries as high citation and relevance may be in conflict as objectives.     

Title characteristics and citations in economics

We provide a view of the literature aging features in the sciences and social sciences, at different aggregation levels, of major fields, subfields, journals and individual papers and from different perspectives. Against to the wide belief that scientific literature may become more rapidly obsolete, we found that, in general, the share of more recent references were distinctly lower in 2014 than that in 1992, which holds for all aggregation levels. As exceptions, the subfields related to Chemistry and the subfield energy and fuels, have shown a clear trend to cite more recent literature than older articles. Particle and nuclear physics and astronomy and astrophysics, the two subfields which strongly rely on e-print archives, have shown a ‘polarization’ tendency of reference distribution. Furthermore, we stress that it is very important to measure the Price Index at the paper level to account for differences between the documents published in the same journals and (sub-)fields.     

An item-by-item subject classification of papers published in multidisciplinary and general journals using reference analysis

A serious shortcoming of bibliometric studies based on the(Social) Science (s) Citation Index is the lack of an universally applicable subject classification scheme as individual papers are concerned. Subject classification of papers on the basis of assigning journals to subject categories (like those found in the various supplements of ISI databases) works well in case of highly specialised journals, but fails for multidisciplinary journals such asNature, Science andPNAS—and so far as subfields are taken into consideration-also for “general” journals (e.g.JACS orAngewandte Chemie). This study presents the results of a pilot project attempting to overcome this shortcoming by delimiting the subject of papers published in multidisciplinary and general journals by an item-by-item subject classification scheme, where assignment is based on the analysis of the subject classification of reference literature. The results clearly confirmed the conclusions of earlier studies by the authors in the field of reference analysis. For the really important journals (sufficiently high number of annual publications and high impact with respect to the field), the share of classifiable papers was surprisingly high, and the assignment proved reliable as well. Since papers in the leading general and multidisciplinary journals are frequently citing general and multidisciplinary journals, an iterated application of the procedure is expected to increase the number of classifiable publications. The results of the new methodology may improve the validity of bibliometric studies for research evaluation purposes.     

The unit of analysis (objects of study) in bibliometrics and scientometrics

Slow development of bibliometric theory may be due in part to neglect of the unit of analysis — the objects described by variables and about which inferences are made. Problems include: inferences are often made on units other than those sampled, leading to inappropriate conclusions; units in literature reviews and meta-analysis are often not comparable, thus hindering cumulation of knowledge; confusion when names of sampling units in one study might also be the names of variables in other studies — e.g., no. of citations (variable) topapers (sampling unit) and no. ofpapers (varible) in journals (sampling unit); loss of information about the unit of analysis, means and variances when data are aggregated. If theory is to advance, scientometrics needs a generic definition of the unit of analysis, a complete list of all known units — classified and structured, meta-analyses, reporting standards — especially when data are aggregated, clear indications of data level (nominal, ordinal, interval, ratio), conventions for including units in titles, abstracts and keyword or subject indexes.     

Research output and transnational cooperation in physics subfields: A multidimensional analysis

This paper compares the profiles of research output and transnational cooperation (as revealed through multicountry publications) of thirty six countries in ten subfields of Physics during the period 1981–1985. The data for comparative analysis were taken fromBraun et al. Since raw counts of publications are confounded by the size of the countries and the size of the research fields, this comparison is made, using relative indicators — activity index and collaboration index. The structures of research output and transnational cooperation are analyzed through Correspondence Analysis, which leads to the identification of countries with similar profiles (of research output and transnational cooperation) and the spatial representation of countries and Physics subfields. The configurations of research output and transnational cooperation are compared to assess the concordance between the policies of these countries for research and transnational cooperation in Physics.     

Scientometric analysis of nature, the journal

300,000 reports inNature during the 1869–1998 period have been reviewed. The distribution of articles by subfields was determined. Additional sources of information were several journals on analytical chemistry and papers at the Pittsburg conference series during 1950–1999. The methodology used is based on the analysis of the average age of employed instruments. The agreement between scientometric data from various sources of information depends on the development stage of the field of science. Calculated and measured scientometric curves were compared. One of the key trends in the development of basic sciences, namely, the increase of articles dealing with instrumental analytical chemistry, inNature is revealed. The research was supported by the Russian Foundation of Basic Research (Project No. 97-06-80163a) and State Target Programme "Integracia" (Project No. 670).     

Citation expectations: are they realized? Study of the Matthew index for Russian papers published abroad

We consider the “Matthew effect” in the citation process which leads to reallocation (or misallocation) of the citations received by scientific papers within the same journals. The case when such reallocation correlates with a country where an author works is investigated. Russian papers in chemistry and physics published abroad were examined. We found that in both disciplines in about 60% of journals Russian papers are cited less than average ones. However, if we consider each discipline as a whole, citedness of a Russian paper in physics will be on the average level, while chemistry publications receive about 16% citations less than one may expect from the citedness of the journals where they appear. Moreover, Russian chemistry papers mostly become undercited in the leading journals of the field. Characteristics of a “Matthew index” indicator and its significance for scientometric studies are also discussed.     

The earth and planetary sciences in science during the twentieth century

The earth and planetary sciences have shown remarkable changes during the present century. The relative coverage of earth and earth-planetary science in the journalScience (from the USA) was studied quantitatively at 5-year intervals for the period 1900–1976. Similar data, but more widely spaced, (10-year intervals) were obtained from the journalNature (from Great Britain) as corroboration.It was found in both journals that the relative attention given to earth science and to the combination of earth and planetary sciences dropped through the century to a low point about 1955. Thereafter the trend reversed, with both of these elements rising almost twice as rapidly as they had previously fallen. A comparison with previous work on the production of American periodical literature showed similar trends but a consistently greater proportion of coverage of these subjects inScience than that in the literature, suggesting that the former is reflecting a wider spectrum of impact of these subjects than is the latter. General science journals may be a better indicator of impact of a science than is the specialized literature.The similarity of results in the two journals indicates that the idea of patterns in world science is a valid one, in which the USA and Great Britain belong to a common pattern.     

Estimates of the annual total number of titles on medicine and its disciplines and scientific productivity of physicians

Two scientometric indices are reviewed: number of printed scientific works per 100 specialists per year and number of scientific journals per 1000 specialists. In 1973–1977 Brazilian chemists and pharmacologists published 15.8 scientific works per 100 specialists per year, in 1981–1985 Japanese physicians — 17.1 ones, in 1968–1986 Czechoslovakian physicians —17.1 ones, in 1978–1986 Hungarian physicians — 18.3 ones, in 1963–1979 Polish physicians — 18.5 ones, in 1983 Yugoslavian physicians — 20.1 titles per 100 specialists. In 1986 in USA 7.2 biomedical journals were issued per 1000 physicians, in Japan — 3.4 ones, in Spain —1.8 biomedical journals per 1000 physicians. In 1986 in USA 6.8 dental periodicals were published per 1000 dentists, Great Britain — 3.0 ones, in Canada — 2.6 ones, in Spain — 2.0 dental journals. The total number of world's biomedical articles and books' titles was 535,000 in 1967, 628,000 in 1972, 820,000 in 1978, 1.01 million ones in 1983 and 1.13 million titles in 1986.     

Assessing stem cell research productivity

Honour Index (HoI), a method to evaluate research performance within different research fields, was derived from the impact factor (IF). It can be used to rate and compare different categories of journals. HoI was used in this study to determine the scientific productivity of stem cell research in the Asian Four Dragons (Hong Kong, Singapore, South Korea and Taiwan) from 1981 to 2001. The methodology applied in this study represents a synthesis of universal indicator studies and bibliometric analyses of subfields at the micro-level. We discuss several comparisons, and conclude the developmental trend in stem cell research for two decades. This revised version was published online in August 2006 with corrections to the Cover Date.