Ranking journals: could Google Scholar Metrics be an alternative to Journal Citation Reports and Scimago Journal Rank?

The launch of Google Scholar Metrics as a tool for assessing scientific journals may be serious competition for Thomson Reuters' Journal Citation Reports, and for the Scopus‐powered Scimago Journal Rank. A review of these bibliometric journal evaluation products is performed. We compare their main characteristics from different approaches: coverage, indexing policies, search and visualization, bibliometric indicators, results analysis options, economic cost, and differences in their ranking of journals. Despite its shortcomings, Google Scholar Metrics is a helpful tool for authors and editors in identifying core journals. As an increasingly useful tool for ranking scientific journals, it may also challenge established journals products.     

Information Sources and Indicators for the Assessment of Journal Reputation and Impact

This guide describes several information sources that can be used to assist faculty interested in quantitative and qualitative assessments of journal reputation and scholarly impact: Journal Citation Reports, Eigenfactor, Google Scholar Metrics, Elsevier Journal Metrics, Excellence in Research for Australia, Cabell’s International, Web of Science, Scopus, Google Scholar, and Beall’s List. It also introduces the indicators most often used to represent citation impact: impact factor, article influence score, eigenfactor, h5-index, source normalized impact per paper, impact per publication, and SCImago journal rank. Methods of assessing the influence of individual articles are also presented, along with strategies for the identification of predatory or low-quality journals.     

Ranking of library and information science researchers: Comparison of data sources for correlating citation data,and expert judgments

This paper studies the correlations between peer review and citation indicators when evaluating research quality in library and information science (LIS). Forty-two LIS experts provided judgments on a 5-point scale of the quality of research published by 101 scholars; the median rankings resulting from these judgments were then correlated with h-, g- and H-index values computed using three different sources of citation data: Web of Science (WoS), Scopus and Google Scholar (GS). The two variants of the basic h-index correlated more strongly with peer judgment than did the h-index itself; citation data from Scopus was more strongly correlated with the expert judgments than was data from GS, which in turn was more strongly correlated than data from WoS; correlations from a carefully cleaned version of GS data were little different from those obtained using swiftly gathered GS data; the indices from the citation databases resulted in broadly similar rankings of the LIS academics; GS disadvantaged researchers in bibliometrics compared to the other two citation database while WoS disadvantaged researchers in the more technical aspects of information retrieval; and experts from the UK and other European countries rated UK academics with higher scores than did experts from the USA.     

A Comparative Citation Analysis of Web of Science,Scopus, and Google Scholar

This article presents the results of a comparative study of Web of Science (WoS), Scopus, and Google Scholar (GS) for a set of 15 business and economics journals. Citations from the three sources were analyzed to determine whether one source is better than another, or whether a new database such as Scopus, or a free database such as GS could replace WoS. The authors concluded that scholars might want to use alternative tools collectively to get a more complete picture of the scholarly impact of an article.     

Google Scholar's Coverage of the Engineering Literature 10 years Later

In 2008 Meier and Conkling first tested Google Scholar's coverage of the engineering literature against citations gathered from the Compendex database. Since that time, other studies have used the same methodology and found improvement in Google Scholar's coverage. This study uses engineering dissertations from Proquest Dissertations & Theses to create a data set of citations for the comparison of fee-based databases, Compendex and Scopus, against Google Scholar. From 1950 to 2017 Google Scholar outperformed both Compendex and Scopus in discoverability of citations in nine engineering subjects. These results have implications for collection management and information literacy program planning for librarians.     

Can Google Scholar and Mendeley help to assess the scholarly impacts of dissertations?

Dissertations can be the single most important scholarly outputs of junior researchers. Whilst sets of journal articles are often evaluated with the help of citation counts from the Web of Science or Scopus, these do not index dissertations and so their impact is hard to assess. In response, this article introduces a new multistage method to extract Google Scholar citation counts for large collections of dissertations from repositories indexed by Google. The method was used to extract Google Scholar citation counts for 77,884 American doctoral dissertations from 2013 to 2017 via ProQuest, with a precision of over 95%. Some ProQuest dissertations that were dual indexed with other repositories could not be retrieved with ProQuest-specific searches but could be found with Google Scholar searches of the other repositories. The Google Scholar citation counts were then compared with Mendeley reader counts, a known source of scholarly-like impact data. A fifth of the dissertations had at least one citation recorded in Google Scholar and slightly fewer had at least one Mendeley reader. Based on numerical comparisons, the Mendeley reader counts seem to be more useful for impact assessment purposes for dissertations that are less than two years old, whilst Google Scholar citations are more useful for older dissertations, especially in social sciences, arts and humanities. Google Scholar citation counts may reflect a more scholarly type of impact than that of Mendeley reader counts because dissertations attract a substantial minority of their citations from other dissertations. In summary, the new method now makes it possible for research funders, institutions and others to systematically evaluate the impact of dissertations, although additional Google Scholar queries for other online repositories are needed to ensure comprehensive coverage.     

Altmetrics of South African Journals: Implications for Scholarly Impact of South African Research

The purpose of the study was to investigate and compare the social media (SM) impact of 273 South Africa Post-Secondary Education accredited journals, which are recognised by the Department of Higher Education and Training of South Africa for purposes of financial support. We used multiple sources to extract data for the study, namely, Altmetric.com, Google Scholar (GS), Scopus (through SCImago) and the Thomson Reuters (TR) Journal Citation Reports (JCR). Data was analysed to determine South African journals’ presence in and impact on SM as well as to contrast SM visibility and impact with the citation impact in GS, JCR and Scopus. The Spearman correlation test was performed to compare the impact of the journals on SM and other sources. The results reveal that 2923 articles published in 122 of the 273 South African (SA) journals have received at least one mention in SM; the most commonly used SM platforms were Twitter and Facebook; the journals indexed in the TR’s citation indexes and Scopus performed much better, in terms of their average altmetrics, than non-TR and non-Scopus indexed journals; and there were weak to moderate relationships among different types of altmetrics and citation-based measures, thereby implying different kinds of journal impacts on SM when compared to the scholarly impact reflected in citation databases. In conclusion, South African journals’ impact on SM, just as is the case with countries with similar economies, is minimal but has shown signs of growth.     

多源数据的期刊复合引文分析均值方法探析

[目的/意义] 鉴于Scopus、Web of Science(WoS)与Google Scholar(GS)3个单源数据库在计量学研究和应用中的局限,发展综合利用多源数据信息的复合型引文分析方法可为计量学分析提供一种补充思路。[方法/过程] 以期刊总被引次数这一底层参量为切入点,用图书情报学国际期刊2009-2014年数据为实证基础,尝试对多源数据复合引文算术均值、几何均值及调和均值方法进行比较讨论。[结果/结论] 结果发现,算术均值、几何均值和调和均值虽有差异,但亦有线性关联,应用中可选其一;累计算术均值、几何均值和调和均值与期刊数之间未证实存在布拉德福定律,但在期刊数量等同的三分区内,累计被引均值满足形如n²:n:1的经验分布;多源数据复合引文与单个数据库引文的期刊排名差异呈现"两端小、中间大"之现象;期刊的算术均值排名与GS排名结果更接近,几何均值排名则与Scopus相似度更高,而调和均值与WoS的排名差异最小。     

Using the Web for research evaluation: The Integrated Online Impact indicator

Previous research has shown that citation data from different types of Web sources can potentially be used for research evaluation. Here we introduce a new combined Integrated Online Impact (IOI) indicator. For a case study, we selected research articles published in the Journal of the American Society for Information Science & Technology (JASIST) and Scientometrics in 2003. We compared the citation counts from Web of Science (WoS) and Scopus with five online sources of citation data including Google Scholar, Google Books, Google Blogs, PowerPoint presentations and course reading lists. The mean and median IOI was nearly twice as high as both WoS and Scopus, confirming that online citations are sufficiently numerous to be useful for the impact assessment of research. We also found significant correlations between conventional and online impact indicators, confirming that both assess something similar in scholarly communication. Further analysis showed that the overall percentage for unique Google Scholar citations outside the WoS were 73% and 60% for the articles published in JASIST and Scientometrics, respectively. An important conclusion is that in subject areas where wider types of intellectual impact indicators outside the WoS and Scopus databases are needed for research evaluation, IOI can be used to help monitor research performance.     

国外Google Scholar研究现状的调研与分析

以引文数据库Web of Science以及Scopus为文献源,采用文献计量学的方法,针对2004年至今的以Google Scholar为研究主题的文献,从文献量及年代分布、文献类型及语种、作者、期刊、文献被引和主题等方面进行分析,揭示Google Scholar的研究现状。     

Google Scholar Usage: An Academic Library's Experience

Google Scholar is a free service that provides a simple way to broadly search for scholarly works and to connect patrons with the resources libraries provide. The researchers in this study analyzed Google Scholar usage data from 2006 for three library tools at San Francisco State University: SFX link resolver, Web Access Management proxy server, and ILLiad interlibrary loan server. Overall, the data suggested that Google Scholar had become a very useful resource in the library and was a significant addition to the library's collection of research databases. SFX data revealed requests from Google Scholar grew ten-fold from 2006 to 2011, and that Google Scholar became the top-ranked SFX source for requests in 2011. Library patrons favored Google Scholar over San Francisco State University's federated search tool, MetaLib, and it has become an important source for interlibrary loan requests. Analysis of San Francisco State University usage data will assist other libraries in their decisions about the implementation of Google Scholar.     

Ranking marketing journals using the Google Scholar-based hg-index

This paper provides a ranking of 69 marketing journals using a new Hirsch-type index, the hg-index which is the geometric mean of hg. The applicability of this index is tested on data retrieved from Google Scholar on marketing journal articles published between 2003 and 2007. The authors investigate the relationship between the hg-ranking, ranking implied by Thomson Reuters’ Journal Impact Factor for 2008, and rankings in previous citation-based studies of marketing journals. They also test two models of consumption of marketing journals that take into account measures of citing (based on the hg-index), prestige, and reading preference.     

Google Scholar Goes to School: The Presence of Google Scholar on College and University Web Sites

This study measured the degree of Google Scholar adoption within academia by analyzing the frequency of Google Scholar appearances on 948 campus and library Web sites, and by ascertaining the establishment of link resolution between Google Scholar and library resources. Results indicate a positive correlation between the implementation of Google Scholar link resolution and the degree of Google Scholar adoption.     

Google Scholar,Web of Science,and Scopus: A systematic comparison of citations in 252 subject categories

Despite citation counts from Google Scholar (GS), Web of Science (WoS), and Scopus being widely consulted by researchers and sometimes used in research evaluations, there is no recent or systematic evidence about the differences between them. In response, this paper investigates 2,448,055 citations to 2299 English-language highly-cited documents from 252 GS subject categories published in 2006, comparing GS, the WoS Core Collection, and Scopus. GS consistently found the largest percentage of citations across all areas (93%–96%), far ahead of Scopus (35%–77%) and WoS (27%–73%). GS found nearly all the WoS (95%) and Scopus (92%) citations. Most citations found only by GS were from non-journal sources (48%–65%), including theses, books, conference papers, and unpublished materials. Many were non-English (19%–38%), and they tended to be much less cited than citing sources that were also in Scopus or WoS. Despite the many unique GS citing sources, Spearman correlations between citation counts in GS and WoS or Scopus are high (0.78-0.99). They are lower in the Humanities, and lower between GS and WoS than between GS and Scopus. The results suggest that in all areas GS citation data is essentially a superset of WoS and Scopus, with substantial extra coverage.     

Convergent validity of bibliometric Google Scholar data in the field of chemistry—Citation counts for papers that were accepted by Angewandte Chemie International Edition or rejected but published elsewhere,using Google Scholar,Science Citation Index,Scopus, and Chemical Abstracts

Examining a comprehensive set of papers (n = 1837) that were accepted for publication by the journal Angewandte Chemie International Edition (one of the prime chemistry journals in the world) or rejected by the journal but then published elsewhere, this study tested the extent to which the use of the freely available database Google Scholar (GS) can be expected to yield valid citation counts in the field of chemistry. Analyses of citations for the set of papers returned by three fee-based databases – Science Citation Index, Scopus, and Chemical Abstracts – were compared to the analysis of citations found using GS data. Whereas the analyses using citations returned by the three fee-based databases show very similar results, the results of the analysis using GS citation data differed greatly from the findings using citations from the fee-based databases. Our study therefore supports, on the one hand, the convergent validity of citation analyses based on data from the fee-based databases and, on the other hand, the lack of convergent validity of the citation analysis based on the GS data.     

A methodological issue concerning the use of Social Sciences Citation Index Journal Citation Reports impact factor data for journal ranking

Following a brief introduction of citation-based journal rankings as potential serials management tools, the most frequently used citation measure—impact factor—is explained. This paper then demonstrates a methodological bias inherent in averaging Social Sciences Citation Index Journal Citation Reports (SSCI JCR) impact factor data from two or more consecutive years. A possible method for correcting the bias, termed adjusted impact factor, is proposed. For illustration, a set of political science journals is ranked according to three different methods (crude averaging, weighted averaging, and adjusted impact factor) for combining SSCI JCR impact factor data from successive years. Although the correlations among the three methods are quite high, one can observe noteworthy differences in the rankings that could impact on collection development decisions.     

Academic Librarians,Information Overload,and the Tao of Discovery

This article explores the meaning of web-scale discovery and argues for the need to formulate a philosophy of discovery (consistent with library values) before using and deploying a discovery tool to make it easier to achieve goals and objectives. It also focuses on how user behavior and the success of Google Scholar can help guide us in improving these tools. At the same time, the essay describes the limitations of discovery tools and their perceived role in contributing to information overload.     

Standing on the Shoulders of Libraries: A Holistic and Rhetorical Approach to Teaching Google Scholar

ABSTRACT

In order to understand better and explain the practices of Google Scholar, this essay takes a rhetorical and holistic look at the search technology, language, and sociopolitical implications of the Google Scholar interface as well as the connection between Google Scholar and the actions of the Google Corporation. The relationship between Google Scholar and the academic library is also explored. In addition, the essay offers ways to encourage students to undertake this kind of critique in the information literacy classroom.