Query expansion methods for collaborative information retrieval

Information Retrieval Systeme haben in den letzten Jahren nur geringe Verbesserungen in der Retrieval Performance erzielt. Wir arbeiten an neuen Ans?tzen, dem sogenannten Collaborativen Information Retrieval (CIR), die das Potential haben, starke Verbesserungen zu erreichen. CIR ist die Methode, mit der durch Ausnutzen von Informationen aus früheren Anfragen die Retrieval Peformance für die aktuelle Anfrage verbessert wird. Wir haben ein eingeschr?nktes Szenario, in dem nur alte Anfragen und dazu relevante Antwortdokumente zur Verfügung stehen. Neue Ans?tze für Methoden der Query Expansion führen unter diesen Bedingungen zu Verbesserungen der Retrieval Performance . The accuracy of ad-hoc document retrieval systems has reached a stable plateau in the last few years. We are working on so-called collaborative information retrieval (CIR) systems which have the potential to overcome the current limits. We define CIR as a task, where an information retrieval (IR) system uses information gathered from previous search processes from one or several users to improve retrieval performance for the current user searching for information. We focus on a restricted setting in CIR in which only old queries and correct answer documents to these queries are available for improving a new query. For this restricted setting we propose new approaches for query expansion procedures. We show how CIR methods can improve overall IR performance.

CR Subject Classification H.3.3     

信息检索扩展技术研究

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国内外联想式信息检索研究综述

本文通过对国内外联想式信息检索的相关研究进行文献调查，总结国内外联想式信息检索研究的概况和存在的问题，并对未来研究方向进行展望。     

浅析基于内容的视频信息检索技术

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对互联网信息检索教学的探讨

从培养学生信息意识和查找信息的能力出发,比较了高校“文献检索与利用”教材与信息管理专业信息检索教材中有关互联网信息检索方面内容的异同点,在总结教学方法的基础上提出改进互联网信息检索教学内容和方法的建议。     

基于网络的信息检索教学设计

随着网络的发展与教学环境的变化,信息检索的教学方式与教学内容发生了很大变化.文章对网络环境下高校信息检索的教育背景及其重要性进行分析,并对提高信息检索教育提出对策和建议.     

基于Agent的信息检索课程网络教学系统设计

Agent是人工智能和计算机软件领域中一种新兴的技术,其在远程教育中的应用具有很大的优越性.文章在分析传统的基于web信息检索课远程教育不足的基础上,探讨了用Agent思想解决远程教育的问题,并设计了一个基于Agent的信息检索课教学系统模型.     

因特网上专利信息的检索

文章首先介绍了中、外专利信息的网络检索,并通过对主要的几个专利信息检索网站进行比较,得出了检索中、美、欧、日、加等国专利信息比较理想的途径。     

Collection-based compound noun segmentation for Korean information retrieval

Compound noun segmentation is a key first step in language processing for Korean. Thus far, most approaches require some form of human supervision, such as pre-existing dictionaries, segmented compound nouns, or heuristic rules. As a result, they suffer from the unknown word problem, which can be overcome by unsupervised approaches. However, previous unsupervised methods normally do not consider all possible segmentation candidates, and/or rely on character-based segmentation clues such as bi-grams or all-length n-grams. So, they are prone to falling into a local solution. To overcome the problem, this paper proposes an unsupervised segmentation algorithm that searches the most likely segmentation result from all possible segmentation candidates using a word-based segmentation context. As word-based segmentation clues, a dictionary is automatically generated from a corpus. Experiments using three test collections show that our segmentation algorithm is successfully applied to Korean information retrieval, improving a dictionary-based longest-matching algorithm.

基于信息素质教育的高校文献检索课改革

简述了文献检索课在信息素质教育中的重要性,分析了高校文献检索课的现状和问题,对如何充分发挥文献检索课在信息素质教育中的重要作用提出了建议。     

网络信息检索之我见

针对目前网络信息检索中检索效率低下的问题,提出三种解决方法:分类浏览式检索方式与传统分类法的结合;利用控制技术提高关键词检索的效率;建立网站自身信息的检索机制.     

多媒体信息检索的有效性度量方法研究

多媒体信息检索是根据相似性度量而不是精确匹配技术进行检索的。有效性是测量多媒体检索系统性能的一个主要参数，本文着重介绍了几种常见的有效性度量方法，讨论了各自的优点、缺点和适用性，并给出了一个新的有效性度量方法。     

基于Blackboard教学平台的医学文献检索课教学模式改革

比较了传统教学模式和网络教学模式的优缺点,指出了医学文献检索课应采取传统教学模式和网络辅助教学模式相结合的模式,详细介绍了Blackboard教学平台的功能模块在构建医学文献检索课新型教学模式的具体应用。     

医学信息检索对医学文稿编辑加工的作用

介绍医学信息检索相关数据库,探讨医学信息检索在参考文献等编辑加工中的作用.认为医学编辑应掌握关键词、医学信息检索技能,熟悉常用医学数据库的检索,利用医学信息检索提高工作效率及编校质量.     

基于Blackboard网络教学平台医学信息检索课考试方法的改革

以华北煤炭医学院信息检索教研室利用Blackboard网络教学平台进行考试方法改革的实践为例,介绍了Blackboard网络教学平台测试功能的使用,并对网络考试方法改革进行了探讨     

An effective and efficient results merging strategy for multilingual information retrieval in federated search environments

Multilingual information retrieval is generally understood to mean the retrieval of relevant information in multiple target languages in response to a user query in a single source language. In a multilingual federated search environment, different information sources contain documents in different languages. A general search strategy in multilingual federated search environments is to translate the user query to each language of the information sources and run a monolingual search in each information source. It is then necessary to obtain a single ranked document list by merging the individual ranked lists from the information sources that are in different languages. This is known as the results merging problem for multilingual information retrieval. Previous research has shown that the simple approach of normalizing source-specific document scores is not effective. On the other side, a more effective merging method was proposed to download and translate all retrieved documents into the source language and generate the final ranked list by running a monolingual search in the search client. The latter method is more effective but is associated with a large amount of online communication and computation costs. This paper proposes an effective and efficient approach for the results merging task of multilingual ranked lists. Particularly, it downloads only a small number of documents from the individual ranked lists of each user query to calculate comparable document scores by utilizing both the query-based translation method and the document-based translation method. Then, query-specific and source-specific transformation models can be trained for individual ranked lists by using the information of these downloaded documents. These transformation models are used to estimate comparable document scores for all retrieved documents and thus the documents can be sorted into a final ranked list. This merging approach is efficient as only a subset of the retrieved documents are downloaded and translated online. Furthermore, an extensive set of experiments on the Cross-Language Evaluation Forum (CLEF) () data has demonstrated the effectiveness of the query-specific and source-specific results merging algorithm against other alternatives. The new research in this paper proposes different variants of the query-specific and source-specific results merging algorithm with different transformation models. This paper also provides thorough experimental results as well as detailed analysis. All of the work substantially extends the preliminary research in (Si and Callan, in: Peters (ed.) Results of the cross-language evaluation forum-CLEF 2005, 2005).

信息检索课多媒体教学现状研究

多媒体技术已越来越多地被运用于现代教育之中,文章分析了信息检索课多媒体教学的优势与存在的缺陷,并提出相应的措施。