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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.
基于词条权值的相关反馈算法在Web信息检索中的应用   总被引:5,自引:0,他引:5  
相关反馈技术是近年来信息检索技术研究的热点.本文首先介绍了传统信息检索技术的原理和存在的问题;接着概述了相关反馈技术的原理与过程;随后介绍词条及其权值算法并应用到相关反馈技术中去,提高信息检索的效果;最后给出了算法评价的试验结果.  相似文献   

3.
采用提问式融合与相关反馈方法的结合,对现有的TopN文献选取策略研究和分析,提出利用相关度系数选取数量可变的TopN文献进行扩展查询的提问融合算法,即基于可变N反馈的提问融合算法。通过实验对固定N和可变N算法进行对比分析,结果显示可变N反馈在一定程度上可以改进检索性能。  相似文献   

4.
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   

5.
基于Apriori改进算法的局部反馈查询扩展   总被引:1,自引:0,他引:1  
提出面向查询扩展的Apriori改进算法,采用三种剪枝策略,极大提高挖掘效率;针对现有查询扩展存在的缺陷,提出基于Apriori改进算法的局部反馈查询扩展算法,该算法用Apriori改进算法对前列初检文档进行词间关联规则挖掘,提取含有原查询词的词间关联规则,构造规则库,从库中提取扩展词,实现查询扩展。实验结果表明该算法能够提高信息检索性能,与现有算法比较,在相同查全率水平级下其平均查准率有了明显提高。  相似文献   

6.
特征词抽取和相关性融合的伪相关反馈查询扩展   总被引:2,自引:0,他引:2  
针对现有信息检索系统中存在的词不匹配问题,提出一种基于特征词抽取和相关性融合的伪相关反馈查询扩展算法以及新的扩展词权重计算方法。该算法从前列n篇初检局部文档中抽取与原查询相关的特征词,根据特征词在初检文档集中出现的频度以及与原查询的相关度,将特征词确定为最终的扩展词实现查询扩展。实验结果表明,该方法有效,并能提高和改善信息检索性能。  相似文献   

7.
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   

8.
Internet个性化智能信息检索的分析与研究   总被引:9,自引:0,他引:9  
宋玲  马军 《情报学报》2002,21(1):33-37
本文首先对Internet网上信息检索进行了综述与分析 ,针对存在的问题 ,介绍了智能Agents的解决方法 ,最后本文提出了一个多Agents系统的个性化智能信息检索系统的模型 ,该模型集成了神经网络、最好优先算法、信息过滤、相关反馈等多种算法  相似文献   

9.
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   

10.
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   

11.
Relevance feedback is an effective technique for improving search accuracy in interactive information retrieval. In this paper, we study an interesting optimization problem in interactive feedback that aims at optimizing the tradeoff between presenting search results with the highest immediate utility to a user (but not necessarily most useful for collecting feedback information) and presenting search results with the best potential for collecting useful feedback information (but not necessarily the most useful documents from a user’s perspective). Optimizing such an exploration–exploitation tradeoff is key to the optimization of the overall utility of relevance feedback to a user in the entire session of relevance feedback. We formally frame this tradeoff as a problem of optimizing the diversification of search results since relevance judgments on more diversified results have been shown to be more useful for relevance feedback. We propose a machine learning approach to adaptively optimizing the diversification of search results for each query so as to optimize the overall utility in an entire session. Experiment results on three representative retrieval test collections show that the proposed learning approach can effectively optimize the exploration–exploitation tradeoff and outperforms the traditional relevance feedback approach which only does exploitation without exploration.  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.
信息检索系统中的相关反馈技术   总被引:2,自引:0,他引:2  
本文论述了布尔模型、向量空间模型以及概率模型中所采用的相关反馈技术,其中主要集中于检索词权值调整以及查询扩展等两项技术。作者还讨论了相关反馈技术对检索性能影响的评估方法,并提出了相关反馈在实际应用中需要解决的问题。  相似文献   

14.
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   

15.
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   

16.
We propose a hybrid information retrieval (IR) procedure that builds on two well-known IR approaches: data fusion and query expansion via relevance feedback. This IR procedure is designed to exploit the strengths of data fusion and relevance feedback and to avoid some weaknesses of these approaches. We show that our IR procedure is built on postulates that can be justified analytically and empirically. Additionally, we offer an empirical investigation of the procedure, showing that it is superior to relevance feedback on some dimensions and comparable on other dimensions. The empirical investigation also verifies the conditions under which the use of our IR procedure could be beneficial.  相似文献   

17.
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   

18.
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  
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   

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