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1.
Google Scholar Beta检索性能的初步分析 总被引：6，自引：1，他引：6
利用多个医学提问，通过对Google Scholar Beta、PubMed、ISI Science Citation Index Expanded、CrossRef Search、Scirus等工具检索结果的对比，分析 Google Scholar Beta 测试版搜索引擎在学术信息检索中的性能表现，特别是检索的查全率、结果的相关性、文献被引用检索等方面的性能，指出其存在的不足，并对该搜索引擎对图书馆跨库查询方案的影响进行初步探讨。 相似文献
2.
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. 相似文献
3.
The literature shows that students are more likely to begin their search via Google, as it is perceived to be easier and more accessible than other databases or publisher platforms. The invisible web, specifically publisher platforms, is sometimes too difficult for students to access; there are also suggestions that Google Scholar in particular may outperform other paid-for databases. The ease of access and the somewhat misguided notion that Google Scholar has more reliable information than that provided by libraries makes search engines all the more attractive. This culture of searching using a single search box is reflected in the increase in the number of libraries opting for single resource discovery systems such as Summon or Primo, which use a single search covering all the library holdings. The findings suggest that whilst Google Scholar can perform well in some circumstances, it performed only moderately well when compared with LISTA and Summon – the single resource discovery system tested. It was the least successful resource in terms of precision when compared with LISTA, Summon, Emerald and Sage. However, the simplicity of search engines begs the question: will databases and publisher platforms become obsolete? The study concludes that subject specific databases are more effective than search engines, but the complexity of accessing the invisible web is hindering their popularity. 相似文献
4.
Objectives: Map of Medicine is an evidence‐based online clinical knowledge resource. Procured at significant cost by healthcare providers in the UK, Sweden and Denmark, it is important to establish the beneficial impact that investment has had on healthcare practise and, ultimately, on patient outcomes. The objective of this study is to review the evidence for the impact of the Map of Medicine on clinical practice. Methods: A systematic review of peer‐reviewed and grey literature was conducted. Nine healthcare databases, Google Scholar and Google were searched for articles containing the terms ‘map of medicine’. Results: The search identified 133 articles. Eleven of the articles identified met the inclusion criteria. The main finding of the study is the paucity of evidence available on the impact of the Map of Medicine and the variable quality of that which does exist. There are some encouraging early indications for the Map of Medicine as a tool within service redesign, leading to an increase in appropriate referrals to secondary care, decreased patient waiting times and considerable cost savings. Conclusion: Further research with study designs that can generate high quality evidence for the impact of Map of Medicine is essential in order to support policy decisions. 相似文献
5.
Expert searching in health librarianship: a literature review to identify international issues and Australian concerns 总被引：1，自引：1，他引：0
Lasserre K 《Health information and libraries journal》2012,29(1):3-15
Background: The traditional role of health librarians as expert searchers is under challenge. Objectives: The purpose of this review is to establish health librarians’ views, practices and educational processes on expert searching. Methods: The search strategy was developed in LISTA and then customised for ten other databases: ALISA, PubMed, Embase, Scopus, Web of Science, CINAHL, ERIC, PsycINFO, Cochrane Library and Google Scholar. The search terms were (expert search* OR expert retriev* OR mediated search* OR information retriev*) AND librar*. The searches, completed in December 2010 and repeated in May 2011, were limited to English language publications from 2000 to 2011 (unless seminal works). Results: Expert searching remains a key role for health librarians, especially for those supporting systematic reviews or employed as clinical librarians answering clinical questions. Conclusions: Although clients tend to be satisfied with searches carried out for them, improvements are required to effectively position the profession. Evidence‐based guidelines, adherence to transparent standards, review of entry‐level education requirements and a commitment to accredited, rigorous, ongoing professional development will ensure best practice. 相似文献
6.
Wichor Matthijs Bramer 《Journal of the Medical Library Association》2016,104(2):143-145
Objective
Google Scholar is often used to search for medical literature. Numbers of results reported by Google Scholar outperform the numbers reported by traditional databases. How reliable are these numbers? Why are often not all available 1,000 references shown?Methods
For several complex search strategies used in systematic review projects, the number of citations and the total number of versions were calculated. Several search strategies were followed over a two-year period, registering fluctuations in reported search results.Results
Changes in numbers of reported search results varied enormously between search strategies and dates. Theories for calculations of the reported and shown number of hits were not proved.Conclusions
The number of hits reported in Google Scholar is an unreliable measure. Therefore, its repeatability is problematic, at least when equal results are needed. 相似文献7.
Google Scholar的利用与评价 总被引：5，自引：0，他引：5
Google Scho1ar是一项具有开创性的互联网学术文献搜索服务。介绍了其概况、使用方法及用途，并对其进行了简要的评价。强调中国学者应早日了解并充分利用这一重要工具，为学术工作及研究服务。 相似文献
8.
Objectives: To devise and evaluate a sensitive search strategy to retrieve diagnostic studies on specific diagnostic tests for deep vein thrombosis (DVT). Methods: Systematic reviews on diagnostic tests for DVT were identified and the studies cited by them used to produce a reference set of search results (to be used to evaluate different search strategies). Five existing diagnosis search filters were combined to produce a sensitive search. This combined search was then refined to produce a more specific strategy, which was run on medline and the results were checked against the reference set. This search was too specific and was modified to produce a more balanced final strategy, which was again tested and the results compared with the reference set. The sensitivity of this newly created strategy was compared with the existing diagnosis searches already found. Finally, studies identified by the final search strategy were critically appraised for validity and relevance and the selected articles were compared with those found in the reference set. Results: The final filter retrieved 124 out of 126 references from the reference set. From the search result, 227 cohort studies were selected and 147 of these were not cited in any of the systematic reviews on diagnostic tests for DVT. Conclusions: The search strategy had 98.8% sensitivity. The precision of 8.8%, although low, compares well with other strategies with high sensitivity. Most of the systematic reviews on diagnosing a DVT have omitted a number of high quality articles. 相似文献
9.
Jeffrey Beall 《期刊图书馆员》2013,64(1):40-53
This article critically examines four Google search products (Google Advanced Search, Google News Advanced Search, Google Books Advanced Search, and Google Advanced Scholar Search) and shows how each uses metadata to enhance or improve search results. In addition, the article shows how metadata can increase search precision and recall in information discovery systems. From a library perspective, this article analyzes some of the metadata-enabled features of Google's advanced search pages and compares these features to those found in a typical online library catalog. From a serials perspective, Google News Advanced Search demonstrates how Google indexes news websites, sites that are essentially continuing resources. As Google incorporates more and more metadata functionality into its advanced search pages, they increasingly begin to function more like online library catalogs and less like search pages found in a traditional Internet search engine. The simple search box has many limitations, and like libraries, Google is increasingly creating and offering metadata-enabled search features that improve search precision and recall in its products. 相似文献
10.
Elaine J. Matthews Adrian G. K. Edwards Jackie Barker Michael Bloor Judith Covey Kerenza Hood Roisin Pill IaN. Russell Nigel Stott Clare Wilkinson 《Health information and libraries journal》1999,16(2):112-120
Using the example of communication about risk in a primary care setting, this paper puts forward a method of developing and evaluating a detailed search strategy for locating the literature for a systematic review of a ‘diffuse’ subject. The aim of this paper is to show how to develop a search strategy that maximizes both recall and precision while keeping search outputs manageable. Six different databases were used, namely Medline, Embase, PsychLIT, CancerLIT, Cinahl and Social Science Citation Index (SSCI). The searches were augmented by hand-searching, contacting authors, citation searching and reference lists from included papers. Other databases were searched but yielded no extra references for this subject matter. Of the 99 papers included, 80 were indexed on Medline. The Medline search strategy identified 54 of them and the remaining 26 were located on other databases. The 19 further unique references were found using the other databases and methods of retrieval. A combination of several databases must be used to maximize recall and to increase the precision of searches on individual databases, thus improving the overall efficiency of the search. 相似文献
11.
Objectives: National databases may be useful sources in the production of a systematic review (SR). The aim of this study was to assess the potential benefit of a systematic search in the German database ‘Current Contents Medizin’ (CCMed ). Methods: The study was conducted on the basis of published SRs that included CCMed as a literature source. Eligible SRs were identified through a systematic search in medline , embase and The Cochrane Library. The websites of German Health Technology Assessment agencies were also screened. Citations of primary studies included as relevant in the SRs were extracted and then categorised. Results: The search yielded 52 eligible SRs. A total of 1505 relevant citations were extracted. Seventy‐seven of these articles were published in journals indexed in CCMed . Thirty‐two of the 77 citations were indexed in CCMed , but only eight of the 32 were unique. Of these eight citations, seven were not identified by a systematic search, but by handsearching. Only one unique citation, an observational study, was identified in CCMed by a systematic search. Conclusions: In the production of SRs, a systematic search in CCMed identifies relevant studies only in exceptional cases. Therefore, the routine inclusion of this database in systematic searches does not appear meaningful. 相似文献
12.
Matt Vassar Branden Carr Melissa Kash-Holley Elizabeth DeWitt Chelsea Koller Joshua Day Kimberly Day David Herrmann Matt Holzmann 《Journal of the Medical Library Association》2015,103(4):189-192
Objective
The choice of bibliographic database during the systematic review search process has been an ongoing conversation among information specialists. With newer information sources, such as Google Scholar and clinical trials registries, we were interested in which databases were utilized by information specialists and systematic review researchers.Method
We retrieved 144 systematic reviews and meta-analyses from 4 clinical endocrinology journals and extracted all information sources used during the search processes.Results
Findings indicate that traditional bibliographic databases are most often used, followed by regional databases, clinical trials registries, and gray literature databases.Conclusions
This study informs information specialists about additional resources that may be considered during the search process. 相似文献13.
Google Scholar在科技论文学术查新中的作用 总被引：4，自引：0，他引：4
Google Scholar是建立在Google搜索引擎上直接面向科研需要的学术资源的网络搜索工具,为广大学术查新工作者提供了极其方便的条件.阐述Google Scholar在科技论文学术查新中的作用,并分析其不足之处,提出了弥补方法. 相似文献
14.
Charlie Potter 《图书馆管理杂志》2013,53(1-2):5-28
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. 相似文献
15.
Rebecca B. French 《Journal of Web Librarianship》2019,13(2):156-197
Information about faculty and their publications can be found in library databases such as the Library of Congress Name Authority File, VIAF, WorldCat, and institutional repositories; in identifier registries such as ORCID and ISNI; and on academic social networking sites such as Academia, Google Scholar, and ResearchGate, but the way search engines use such identifiers and profiles is unclear. Therefore, researchers at a large comprehensive university conducted several rounds of web searching before and after the creation and modification of faculty authority records. The sample consisted of 24 faculty and the 35 publications associated with their authorities. The researchers searched for the faculty and their publications on the social networking and identity websites directly, and then used Google, Bing, and Google Scholar to record which of the faculty members’ profiles and publications were found within the top 50 results. Faculty with more profiles were more visible in search engine results, and faculty with authority records ranked more highly in Google. Results related to publication discovery and ranking were more inconclusive, but revealed clear differences between search tools. The implications of this exploratory research can support educational efforts about academic identities and scholarly profiles, begin a research agenda, and inform methodological development surrounding the influence of identity records and academic social networking profiles on web visibility. 相似文献
16.
17.
Jos Antonio Salvador-Olivn Gonzalo Marco-Cuenca Rosario Arquero-Avils 《Journal of the Medical Library Association》2021,109(4):561
Objective:Locating systematic reviews is essential for clinicians and researchers when creating or updating reviews and for decision-making in health care. This study aimed to develop a search filter for retrieving systematic reviews that improves upon the performance of the PubMed systematic review search filter.Methods:Search terms were identified from abstracts of reviews published in Cochrane Database of Systematic Reviews and the titles of articles indexed as systematic reviews in PubMed. Both the precision of the candidate terms and the number of systematic reviews retrieved from PubMed were evaluated after excluding the subset of articles retrieved by the PubMed systematic review filter. Terms that achieved a precision greater than 70% and relevant publication types indexed with MeSH terms were included in the filter search strategy.Results:The search strategy used in our filter added specific terms not included in PubMed''s systematic review filter and achieved a 61.3% increase in the number of retrieved articles that are potential systematic reviews. Moreover, it achieved an average precision that is likely greater than 80%.Conclusions:The developed search filter will enable users to identify more systematic reviews from PubMed than the PubMed systematic review filter with high precision. 相似文献
18.
Background: Search filters have been developed in MEDLINE and EMBASE to help overcome the challenges of searching electronic databases for information on adverse effects. However, little evaluation of their effectiveness has been carried out. Objectives: To measure the sensitivity and precision of available adverse effects search filters in MEDLINE and EMBASE. Methods: A case study systematic review of fracture related adverse effects associated with the use of thiazolidinediones was used. Twelve MEDLINE search strategies and three EMBASE search strategies were tested. Results: Nineteen relevant references from MEDLINE and 24 from EMBASE were included in the review. Four search filters in MEDLINE achieved high sensitivity (95 or 100%) with an improved level of precision from searches without any adverse effects filter. High precision in MEDLINE could also be achieved (up to 53%) using search filters that rely on Medical Subject Headings. No search filter in EMBASE achieved high precision (all were under 5%) and the highest sensitivity in EMBASE was 83%. Conclusions: Adverse effects search filters appear to be effective in MEDLINE for achieving either high sensitivity or high precision. Search filters in EMBASE, however, do not appear as effective, particularly in improving precision. 相似文献
19.
《Journal of Web Librarianship》2013,7(2):94-108
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. 相似文献
20.
Ripple AS 《Medical reference services quarterly》2006,25(2):97-107
Google is the search engine of choice for most Internet users. For a variety of reasons, librarians and other expert searchers do not always use Google to its full potential, even though it provides capabilities not possible in traditional bibliographic databases and other search engines. Applying expert searching principles and practices, such as the use of advanced search operators, information retrieval strategies, and search hedges to Google will allow health sciences librarians to find quality information on the Internet more efficiently and effectively. 相似文献