共查询到18条相似文献，搜索用时 203 毫秒
1.
相关反馈是近年来信息检索领域的研究热点，是自动查询扩展中的一种重要形式，相关反馈主要包括检索词加权和检索词选择。本文介绍了在相关反馈技术中经典的检索词排序算法，对它们带来的性能改进做了比较，并提出了相关反馈的实际应用中需要解决的一些问题。 相似文献
2.
信息检索系统中的用户相关反馈机制 总被引：3，自引：0，他引：3
陈定权 《现代图书情报技术》2002,18(4):33-35
从理论上论述了向量空间模型和概率模型是如何通过相关反馈机制来提高检索性能，还讨论了在不同模型中，相关反馈是如何实现查询式扩展和检索词权值调整的。 相似文献
3.
论文将国外关于概念检索的实现方法进行归类,主要介绍了基于规则的计算机信息检索及其改良方法、构建背景环境、结合推理假设、形式概念分析、概率扩展查询模型、基于概念的相关反馈、合作网以及其他一些相关方法。 相似文献
4.
相关反馈是一种根据用户或系统的相关性判断重构初始检索提问的方法,已被证明可以有效地改进检索效果.具体到学术文献,其引用关系表征了文献内容上的相关性,因而可以为相关反馈提供有价值的辅助信息.本文提出了一种基于引用上下文、文献同被引和文献耦合的相关反馈改进算法.该算法的基本思想包括:利用学术文献的引用上下文信息扩充词包模型(bags of words)进行文本表示;在相关文献判断阶段利用相关文献在引文网络中与其他文献的同被引强度和耦合强度扩充相关文献集合;结合基于聚类的相关反馈思想抽取查询扩展项.实验证明该算法提高了相关反馈效果.此外,相关分析的结果表明文献同被引以及文献耦合强度与文献内容相似度具有显著的相关性. 相似文献
5.
基于伪相关反馈的跨语言查询扩展 总被引：3，自引：2，他引：1
相关反馈是一种重要的查询重构技术,本文分析了两类相关反馈技术,一是按用户是否参与可分为伪相关反馈和交互式相关反馈,二是按作用于查询的方式可分为查询扩展与检索词重新加权.在此基础上,本文重点探讨了将相关反馈技术应用于跨语言信息检索,提出了翻译前查询扩展、翻译后查询扩展、翻译前与翻译后相结合的查询扩展三种方法.最后,本文通过伪相关反馈实验对这三种方法进行了比较,实验结果显示,三种跨语言查询扩展方法都能够有效地提高检索结果的精度,其中翻译后查询扩展方法相对更优越.此外,查询式的长度对不同跨语言查询扩展方法产生着不同程度的影响. 相似文献
6.
英汉交互式跨语言检索系统设计与实现 总被引：1，自引：0，他引：1
吴丹 《现代图书情报技术》2009,3(2):89-95
针对跨语言信息检索的查询翻译歧义性问题,采用交互式系统开发设计方法,对基于相关反馈的跨语言信息检索技术进行研究和分析,提出一个英汉交互式跨语言信息检索系统,实现用户辅助查询翻译、多级用户相关性判断,以及翻译优化与查询扩展等相关反馈功能,结果明显提高了检索效果。 相似文献
7.
Internet上的图像信息检索技术 总被引：1，自引：0，他引：1
Internet上丰富的图像信息 ,给网络信息检索带来了挑战。本文主要从颜色、形状、纹理、语义等方面阐述了Internet上的图像特征提取 ,分析了图像检索的示例查询方法、相似性度量以及相关反馈技术 ,并指出了目前图像检索中存在的问题和今后发展的方向。 相似文献
8.
如何有效的进行生物医学文献检索和信息挖掘,是计算机技术和生物信息技术研究领域中的一个经典课题。本文对生物医学文献中自然语言问题文档,片段,概念和RDF三元组,构建了高效的检索和问答系统。特别的,在文档检索中,我们搭建了基于顺序依赖模型,词向量,和伪相关反馈相结合的通用检索模型;同时,前k个文档被分离为句子和片段,并以此建立检索索引,并基于文档检索模型,完成片段检索;在概念挖掘中,提取生物医学的概念,列出相关的概念属于网络服务的五个数据库链接,通过得分排名得到最终的概念。在CLEF BioASQ几年的评测数据上,我们构造的检索系统都取得了不错的性能。 相似文献
9.
基于用户信息检索相关性反馈模型的研究 总被引：1，自引：0，他引：1
提出通过获取用户建立和更新信息相关反馈模型的思想.通过观察用户在浏览Web页面时所采取的动作来获取的反馈信息,利用检索算法将用户信息量化,并利用这些信息建立与更新用户模型.一方面用户对检索结果的评价输入到用户模型上,另一方面,检索系统通过机器学习跟踪用户信息并优化用户模型. 相似文献
10.
本文提出了一种新的基于相关反馈的跨语言信息检索查询翻译优化技术,就实现该技术的关键步骤"估计检索词在相关文献集合中的翻译概率"设计了4种不同的算法,并通过伪相关反馈实验比较了这4种算法,验证了查询翻译优化技术的有效性.实验结果显示,4种翻译优化算法都能够提高检索结果的精度,其中基于词对齐的翻译算法相对更优越.此外,查询式的长度和检索主题的特征对不同查询翻译优化算法产生着不同程度的影响. 相似文献
11.
个性化信息检索中的相关反馈技术研究 总被引：3，自引：0，他引：3
简要介绍了相关反馈的研究现状及基本思想,在深入分析相关反馈的实现策略和在不同系统中设计的差别后,提出了相关反馈技术和个性化信息检索结合的模型,最后讨论引入数据融合的思想来进一步改善反馈效果。 相似文献
12.
In Information Retrieval, since it is hard to identify users’ information needs, many approaches have been tried to solve
this problem by expanding initial queries and reweighting the terms in the expanded queries using users’ relevance judgments.
Although relevance feedback is most effective when relevance information about retrieved documents is provided by users, it
is not always available. Another solution is to use correlated terms for query expansion. The main problem with this approach
is how to construct the term-term correlations that can be used effectively to improve retrieval performance. In this study,
we try to construct query concepts that denote users’ information needs from a document space, rather than to reformulate initial queries using the term correlations
and/or users’ relevance feedback. To form query concepts, we extract features from each document, and then cluster the features into primitive concepts that are then used to form
query concepts. Experiments are performed on the Associated Press (AP) dataset taken from the TREC collection. The experimental evaluation
shows that our proposed framework called QCM (Query Concept Method) outperforms baseline probabilistic retrieval model on
TREC retrieval. 相似文献
13.
基于内容的图像检索反馈技术概述 总被引：2，自引：0，他引：2
在对现有的相关反馈算法进行总结的基础上，介绍一些有所改进的反馈算法，同时展示各种算法的基本原理和检索效果。通过对比各种算法的查全率与查准率，展示各种算法的优缺点、应用范围;介绍现有的几个使用相关反馈技术的基于内容的图像检索系统，并针对相关反馈领域的研究预测其有挑战性的发展方向。 相似文献
14.
The application of relevance feedback techniques has been shown to improve retrieval performance for a number of information retrieval tasks. This paper explores incremental relevance feedback for ad hoc Japanese text retrieval; examining, separately and in combination, the utility of term reweighting and query expansion using a probabilistic retrieval model. Retrieval performance is evaluated in terms of standard precision-recall measures, and also using number-to-view graphs. Experimental results, on the standard BMIR-J2 Japanese language retrieval collection, show that both term reweighting and query expansion improve retrieval performance. This is reflected in improvements in both precision and recall, but also a reduction in the average number of documents which must be viewed to find a selected number of relevant items. In particular, using a simple simulation of user searching, incremental application of relevance information is shown to lead to progressively improved retrieval performance and an overall reduction in the number of documents that a user must view to find relevant ones. 相似文献
15.
Medical image retrieval can assist physicians in finding information supporting their diagnosis and fulfilling information needs. Systems that allow searching for medical images need to provide tools for quick and easy navigation and query refinement as the time available for information search is often short. Relevance feedback is a powerful tool in information retrieval. This study evaluates relevance feedback techniques with regard to the content they use. A novel relevance feedback technique that uses both text and visual information of the results is proposed. The two information modalities from the image examples are fused either at the feature level using the Rocchio algorithm or at the query list fusion step using a common late fusion rule. Results using the ImageCLEF 2012 benchmark database for medical image retrieval show the potential of relevance feedback techniques in medical image retrieval. The mean average precision (mAP) is used as the evaluation metric and the proposed method outperforms commonly-used methods. The baseline without feedback reached 16 % whereas the relevance feedback with 20 images reached up to 26.35 % with three steps and when using 100 images up to 34.87 % in four steps. Most improvements occur in the first two steps of relevance feedback and then results start to become relatively flat. This might also be due to only using positive feedback as negative feeback often also improves results after more steps. The effect of relevance feedback in automatically spelling corrected and translated queries is investigated as well. Results without mistakes were better than spell-corrected results but the spelling correction more than double results over non-corrected retrieval. Multimodal relevance feedback has shown to be able to help visual medical information retrieval. Next steps include integrating semantics into relevance feedback techniques to benefit from the structured knowledge of ontologies and experimenting on the fusion of text and visual information. 相似文献
16.
Research on cross-language information retrieval (CLIR) has typically been restricted to settings using binary relevance assessments.
In this paper, we present evaluation results for dictionary-based CLIR using graded relevance assessments in a best match
retrieval environment. A text database containing newspaper articles and a related set of 35 search topics were used in the
tests. First, monolingual baseline queries were automatically formed from the topics. Secondly, source language topics (in
English, German, and Swedish) were automatically translated into the target language (Finnish), using structured target queries.
The effectiveness of the translated queries was compared to that of the monolingual queries. Thirdly, pseudo-relevance feedback
was used to expand the original target queries. CLIR performance was evaluated using three relevance thresholds: stringent,
regular, and liberal. When regular or liberal threshold was used, a reasonable performance was achieved. Using stringent threshold,
equally high performance could not be achieved. On all the relevance thresholds the performance of the translated queries
was successfully raised by pseudo-relevance feedback based query expansion. However, the performance of the stringent threshold
in relation to the other thresholds could not be raised by this method. 相似文献
17.
在阐释图像语义检索中相关反馈的反馈噪声的基础上，分析反馈噪声对语义网络方法的不利影响；提出一种对反馈噪声具有鲁棒性的算法——基于投票思想的相关反馈，并对其性能进行分析；最后指出需进一步研究的问题。 相似文献
18.
基于用户行为的全文检索系统个性化研究 总被引：1，自引：0，他引：1
总结国内有关检索系统个性化研究的现状并进行分析,针对全文检索系统个性化服务方面存在的不足提出了基于用户行为全文检索系统模型,阐释了模型中的三个关键问题,包括相关反馈行为评价体系的制定、用户显式隐式行为的获取、用户兴趣建模和基于行为的相关度算法优化,最后列举了基于用户行为的全文检索系统可提供的四项个性化服务内容,包括个性化用户界面、优化检索策略、个性化检索结果、个性化推荐. 相似文献