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As the volume and variety of information sources continues to grow, there is increasing difficulty with respect to obtaining
information that accurately matches user information needs. A number of factors affect information retrieval effectiveness
(the accuracy of matching user information needs against the retrieved information). First, users often do not present search
queries in the form that optimally represents their information need. Second, the measure of a document’s relevance is often
highly subjective between different users. Third, information sources might contain heterogeneous documents, in multiple formats
and the representation of documents is not unified. This paper discusses an approach for improvement of information retrieval
effectiveness from document databases. It is proposed that retrieval effectiveness can be improved by applying computational
intelligence techniques for modelling information needs, through interactive reinforcement learning. The method combines qualitative
(subjective) user relevance feedback with quantitative (algorithmic) measures of the relevance of retrieved documents. An
information retrieval is developed whose retrieval effectiveness is evaluated using traditional precision and recall. 相似文献
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尽管图书馆自建书目数据库、文摘数据库、全文数据库和多媒体数据库有具体的表现形式,但是独创性较差,致使其著作权保护处于较弱的地位;由于维护公共利益和公民其他基本权利等著作权外部条件的限制,图书馆自建数据库著作权保护也不可能强势. 相似文献
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Background
Systematic reviews risk producing biased conclusions if a comprehensive search to identify eligible studies is not undertaken, but little evidence exists to guide prioritisation of databases to search when resources are limited.Objectives
A systematic review examining interventions for managing frozen shoulder (adhesive capsulitis) was used to investigate the performance of bibliographic databases in identifying the included studies, the smallest combination of databases required to retrieve all included studies, and the performance of the searches themselves.Methods
We calculated the yield of included studies from each of 15 databases, and the recall and precision of each search strategy. We investigated differences between the presence of a record in a database and its retrieval.Results
Thirty of 31 studies were present in at least one database. Yields of individual databases ranged from 0% to 90% (median 23%). Two combinations of databases identified all 30 studies: Cochrane Central Register of Controlled Trials (CENTRAL) and Science Citation Index (SCI); or CENTRAL, MEDLINE and PreMEDLINE.Conclusions
In a systematic review of a range of interventions used to manage frozen shoulder, at least two databases and reference checking were required to retrieve all included studies, but searching for future reviews should not be restricted. 相似文献5.
Deurenberg R Vlayen J Guillo S Oliver TK Fervers B Burgers J;SEARCH Group 《Health information and libraries journal》2008,25(1):23-30
BACKGROUND: Effective literature searching is particularly important for clinical practice guideline development. Sophisticated searching and filtering mechanisms are needed to help ensure that all relevant research is reviewed. PURPOSE: To assess the methods used for the selection of evidence for guideline development by evidence-based guideline development organizations. METHODS: A semistructured questionnaire assessing the databases, search filters and evaluation methods used for literature retrieval was distributed to eight major organizations involved in evidence-based guideline development. RESULTS: All of the organizations used search filters as part of guideline development. The medline database was the primary source accessed for literature retrieval. The OVID or SilverPlatter interfaces were used in preference to the freely accessed PubMed interface. The Cochrane Library, embase, cinahl and psycinfo databases were also frequently used by the organizations. All organizations reported the intention to improve and validate their filters for finding literature specifically relevant for guidelines. DISCUSSION: In the first international survey of its kind, eight major guideline development organizations indicated a strong interest in identifying, improving and standardizing search filters to improve guideline development. It is to be hoped that this will result in the standardization of, and open access to, search filters, an improvement in literature searching outcomes and greater collaboration among guideline development organizations. 相似文献
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基于主成分分析的特色数据库的评价 总被引：3，自引：0，他引：3
以郑州轻工业学院自建16个特色数据库为对象,基于主成分分析原理,采用SPSS软件分析这16个特色数据库评价指标的合理性和科学性。结果表明,评价指标的选择必须考虑指标间是否具有相关性,同时特色库建设的内容考虑的应该是数据库的覆盖的范围和数量、查准率、查全率、更新频率和使用频率、界面友好和方便程度。最重要的是数据库的建设必须以使用者为导向。 相似文献
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Nancy L. Wilczynski Cynthia Lokker Kathleen Ann McKibbon Nicholas Hobson R. Brian Haynes 《Journal of the Medical Library Association》2016,104(1):42-46
Objective
The research attempted to develop search filters for biomedical literature databases that improve retrieval of studies of clinical relevance for the nursing and rehabilitation professions.Methods
Diagnostic testing framework compared machine-culled and practitioner-nominated search terms with a hand-tagged clinical literature database.Results
We were unable to: (1) develop filters for nursing, likely because of the overlapping and expanding scope of practice for nurses in comparison with medical professionals, or (2) develop filters for rehabilitation, because of its broad scope and the profession''s multifaceted understanding of “health and ability.”Conclusions
We found limitations on search filter development for these health professions: nursing and rehabilitation. 相似文献8.
Abstract This study demonstrates how changes in intellectual property law have effects on the value‐creation process of information commodity and related strategies. To explain these effects, three unique economic characteristics of databases as information are focused on: public good, information good, and aggregate good. And, different strategies such as versioning, technical strategies, and limiting the number of consumers and data mingling have been suggested for each characteristic. To examine the value‐création process of databases, a three‐step process has shown: data gathering, selection/arrangement, and presentation. In the legal process, two main rationales, ‘sweat of the brow doctrine’ and ‘originality doctrine’ have suggested protecting database compilations. The ‘sweat of the brow doctrine’ stresses the effort and investment of the compiler. On the contrary, the ‘originality doctrine’ emphasizes the judgment and creativity in the selection and arrangement of the materials comprising the compilation. 相似文献
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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
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OBJECTIVES: This research was conducted to provide new insights on clinical nurses' and nursing students' current use of health resources and libraries and deterrents to their retrieval of electronic clinical information, exploring implications from these findings for health sciences librarians. METHODS: Questionnaires, interviews, and observations were used to collect data from twenty-five nursing students and twenty-five clinical nurses. RESULTS: Nursing students and clinical nurses were most likely to rely on colleagues and books for medical information, while other resources they frequently cited included personal digital assistants, electronic journals and books, and drug representatives. Significantly more nursing students than clinical nurses used online databases, including CINAHL and PubMed, to locate health information, and nursing students were more likely than clinical nurses to report performing a database search at least one to five times a week. CONCLUSIONS AND RECOMMENDATIONS: Nursing students made more use of all available resources and were better trained than clinical nurses, but both groups lacked database-searching skills. Participants were eager for more patient care information, more database training, and better computer skills; therefore, health sciences librarians have the opportunity to meet the nurses' information needs and improve nurses' clinical information-seeking behavior. 相似文献
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Searching for randomised controlled trials and clinical controlled trials in Thai online bibliographical biomedical databases 总被引：1，自引：1，他引：0
Background: Thailand is a poor but highly literate country in South‐East Asia with over 60 million people. A lot of biomedical research is undertaken but dissemination is limited. Objectives: To identify relevant Thai bibliographic databases and investigate accessibility, functionality and content, particularly in relation to randomised controlled trials (RCTs) and clinical controlled trials (CCTs). Methods: A systematic search for institutions productive of research and the databases in their libraries. Search each accessible database in both Thai and English, recording the functionality and content. Assess accessibility of the retrieved RCTs or CCTs by comparing to Pub Med holdings. Results: We found 32 different databases (29 accessible in UK) of various sizes, coverage and functionality but many with unique records of RCTs and CCTs (total, n = 781). Two hundred and nine of 781 trials were accessible on Pub Med (27%). However, 641 of the 781 trial records contain text in both English and Thai (82%) and 112 records were solely English (14%). Conclusions: Those undertaking comprehensive searches for RCTs/CCTs should, in addition to a Pub Med , search the Thai Medical Index and Thai Index Medicus databases, and the Khon Kaen University Library Catalogue. 相似文献
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指出具有独创性的数据库受到法律保护,这就使大量的数据库虽然花费大量金钱和劳动,但依据现行法的规定,投资者的权利无从保护。因此,针对这一问题,及时进行研究和制定相应策略就成为我国当前立法研究的必要。介绍我国的数据库保护现状以及借鉴美国、欧盟的立法经验,探索我国对有关数据库特殊权利予以单独立法保护的途径,并进一步提出立法的原则性构想。 相似文献
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Bert Avau Hans Van Remoortel Emmy De Buck 《Journal of the Medical Library Association》2021,109(4):599
Objective:The aim of this project was to validate search filters for systematic reviews, intervention studies, and observational studies translated from Ovid MEDLINE and Embase syntax and used for searches in PubMed and Embase.com during the development of evidence summaries supporting first aid guidelines. We aimed to achieve a balance among recall, specificity, precision, and number needed to read (NNR).Methods:Reference gold standards were constructed per study type derived from existing evidence summaries. Search filter performance was assessed through retrospective searches and measurement of relative recall, specificity, precision, and NNR when using the translated search filters. Where necessary, search filters were optimized. Adapted filters were validated in separate validation gold standards.Results:Search filters for systematic reviews and observational studies reached recall of ≥85% in both PubMed and Embase. Corresponding specificities for systematic review filters were ≥96% in both databases, with a precision of 9.7% (NNR 10) in PubMed and 5.4% (NNR 19) in Embase. For observational study filters, specificity, precision, and NNR were 68%, 2%, and 51 in PubMed and 47%, 0.8%, and 123 in Embase, respectively. These filters were considered sufficiently effective. Search filters for intervention studies reached a recall of 85% and 83% in PubMed and Embase, respectively. Optimization led to recall of ≥95% with specificity, precision, and NNR of 49%, 1.3%, and 79 in PubMed and 56%, 0.74%, and 136 in Embase, respectively.Conclusions:We report validated filters to search for systematic reviews, observational studies, and intervention studies in guideline projects in PubMed and Embase.com. 相似文献
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相关性研究与情报检索系统评价 总被引：1，自引：0，他引：1
从情报检索系统评价的角度探讨相关性研究发展的历史,分析相关性作为系统性能评价指标的可行性,指出利用相关性评价情报检索系统性能实验的优势及不足,展望相关性研究发展的趋势。 相似文献
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《The Reference Librarian》2013,54(39):85-97
The proliferation of electronic information sources has added new dimensions to building library reference collections. As reference librarians select titles for their collections, they must also choose the most appropriate medium. For some information the choices include print, microforms, CD-ROM databases, online hosts, or locally mounted databases. Factors involved in the selection of the appropriate medium include database costs, licensing agreements, hardware/software requirements, retrieval modes, system capabilites, and information transfer. Integrating the new services into existing structures so that library patrons can derive the maximum benefit from the availability of the databases is a primary concern. 相似文献
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A comprehensive analysis of Germany's chemical periodicals included in the databases of the two leading international information-analytical systems Scopus and Web of Science, a bibliographic database Ulrich's Periodicals Directory, as well as in the database of All-Russia Institute for Scientific and Technical Information of Russian Academy of Sciences (VINITI RAS), was performed. An analytical procedure developed made it possible to analyze effectively different domains of publications, both common to the three databases, as well as various combinations of interest, inter alia an array which was not included in any of them. The data covering the ratings of periodicals were presented basing on generally accepted international scientometric indicators and on processing degree value for the VINITI database. Distribution of subject areas, publishing houses, language of editions, internet access availability were determined. The research results allowed to summarize proposals for optimization of VINITI database workflow in the area studied. 相似文献
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J M Nixon 《Medical reference services quarterly》1989,8(3):27-35
This study compares six databases which contain information on applied and clinical human nutrition: AGRICOLA, BIOSIS, CAB ABSTRACTS, EMBASE, MEDLINE, and SCI-SEARCH. Five research questions were searched, and the results were compared to identify the database of first choice and to determine the degree of overlap among the databases. Results indicate that for most of the human nutrition questions searched, MEDLINE was the most productive database. However, MEDLINE alone only uncovered 24% to 69% of the citations available. A combination of MEDLINE and at least one other database is recommended. The results of this study suggest that for most human nutrition questions, AGRICOLA is the best file to complement MEDLINE. 相似文献
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Tuomo Korenius Jorma Laurikkala Martti Juhola Kalervo Järvelin 《Information Retrieval》2006,9(1):33-53
Search facilitated with agglomerative hierarchical clustering methods was studied in a collection of Finnish newspaper articles
(N = 53,893). To allow quick experiments, clustering was applied to a sample (N = 5,000) that was reduced with principal components analysis. The dendrograms were heuristically cut to find an optimal partition,
whose clusters were compared with each of the 30 queries to retrieve the best-matching cluster. The four-level relevance assessment
was collapsed into a binary one by (A) considering all the relevant and (B) only the highly relevant documents relevant, respectively.
Single linkage (SL) was the worst method. It created many tiny clusters, and, consequently, searches enabled with it had high
precision and low recall. The complete linkage (CL), average linkage (AL), and Ward's methods (WM) returned reasonably-sized
clusters typically of 18–32 documents. Their recall (A: 27–52%, B: 50–82%) and precision (A: 83–90%, B: 18–21%) was higher
than and comparable to those of the SL clusters, respectively. The AL and WM clustering had 1–8% better effectiveness than
nearest neighbor searching (NN), and SL and CL were 1–9% less efficient that NN. However, the differences were statistically
insignificant. When evaluated with the liberal assessment A, the results suggest that the AL and WM clustering offer better
retrieval ability than NN. Assessment B renders the AL and WM clustering better than NN, when recall is considered more important
than precision. The results imply that collections in the highly inflectional and agglutinative languages, such as Finnish,
may be clustered as the collections in English, provided that documents are appropriately preprocessed. 相似文献