共查询到17条相似文献,搜索用时 125 毫秒
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全文检索中的汉语自动分词及其歧义处理 总被引:3,自引:0,他引:3
歧义处理是汉语自动分词的核心问题,汉语自动分词是中文信息检索的基础性课题。目前有基于词典的分词方法、基于统计的分词方法、基于语义的分词方法和基于人工智能的分词方法。自动分词的歧义处理,目前主要有:利用“长词优先”排歧,利用特征词消歧,利用“互信息”和“t-信息差”消歧,利用专家系统分词消歧。参考文献15。 相似文献
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国内中文自动分词技术研究综述 总被引:22,自引:0,他引:22
认为分词是文本自动分类、信息检索、信息过滤、文献自动标引、摘要自动生成等中文信息处理的基础与关键技术之一,中文本身复杂性及语言规则的不确定性,使中文分词技术成为分词技术中的难点.全面归纳中文分词算法、歧义消除、未登录词识别、自动分词系统等研究,总结出当前中文分词面临的难点与研究热点. 相似文献
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中文文本关键词自动抽取方法研究 总被引:6,自引:1,他引:5
随着信息技术的发展,中文电子文本信息资源正以惊人的速度急剧增长.文本自动处理技术,通过自动组织海量文献信息资源,能够为用户提供简易有效的信息检索服务.关键词自动抽取是文本自动处理的基础和核心.汉语的特殊性加剧了中文文本关键词自动抽取的难度.本文提出了一种基于N-gram权重计算和关键词筛选算法的中文文本关键词自动抽取方法.该方法不依赖特定的数据集和中文分词技术,可以有效地抽取出任意单篇文本的关键词,而且通过参数调整,应用系统可以灵活地控制标引深度和标引专指度.实验表明,该方法简单、快速、断词错误率低,标引性能明显优于基于中文分词和TF/IDF的方法,可以满足大规模文本的在线处理要求. 相似文献
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本文论述网络环境下中文网页信息的自动标引技术,具体研究分析了面向信息检索的自动分词与词表技术,提出了一个中文网页自动标引的改进方案,以更好地实现中文网络信息资源的自动处理,最后从文档到知识转变的视角,研究第三代网页内容搜索中应用中文信息自动标引的技术问题。 相似文献
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自动分词技术及其在信息检索中应用的研究 总被引:19,自引:1,他引:18
首先分析了自动分词与自然语言处理、自动分词与信息检索之间的关系, 在此基础上, 介绍了近年来自动分词系统实现的技术原理, 探讨了自动分词技术在信息检索中应用的问题。 相似文献
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Xiangji Huang Fuchun Peng Dale Schuurmans Nick Cercone Stephen E. Robertson 《Information Retrieval》2003,6(3-4):333-362
We propose a self-supervised word segmentation technique for text segmentation in Chinese information retrieval. This method combines the advantages of traditional dictionary based, character based and mutual information based approaches, while overcoming many of their shortcomings. Experiments on TREC data show this method is promising. Our method is completely language independent and unsupervised, which provides a promising avenue for constructing accurate multi-lingual or cross-lingual information retrieval systems that are flexible and adaptive. We find that although the segmentation accuracy of self-supervised segmentation is not as high as some other segmentation methods, it is enough to give good retrieval performance. It is commonly believed that word segmentation accuracy is monotonically related to retrieval performance in Chinese information retrieval. However, for Chinese, we find that the relationship between segmentation and retrieval performance is in fact nonmonotonic; that is, at around 70% word segmentation accuracy an over-segmentation phenomenon begins to occur which leads to a reduction in information retrieval performance. We demonstrate this effect by presenting an empirical investigation of information retrieval on Chinese TREC data, using a wide variety of word segmentation algorithms with word segmentation accuracies ranging from 44% to 95%, including 70% word segmentation accuracy from our self-supervised word-segmentation approach. It appears that the main reason for the drop in retrieval performance is that correct compounds and collocations are preserved by accurate segmenters, while they are broken up by less accurate (but reasonable) segmenters, to a surprising advantage. This suggests that words themselves might be too broad a notion to conveniently capture the general semantic meaning of Chinese text. Our research suggests machine learning techniques can play an important role in building adaptable information retrieval systems and different evaluation standards for word segmentation should be given to different applications. 相似文献
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基于哈希算法的中文分词算法的改进 总被引:1,自引:0,他引:1
中文分词是中文信息处理一个重要的部分,一些应用不仅要准确率,速度也很重要,通过对已有算法的分析,特别是对快速分词算法的分析,本文提出了一种新的词典结构,并根据新的词典给出了新的分词算法,该算法不仅对词首字实现了哈希查找,对词余下的字也实现哈希查找。理论分析和实验结果表明,算法在速度和效率比现有的几种分词算法上有所提高。 相似文献
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Improving English and Chinese Ad-Hoc Retrieval: A Tipster Text Phase 3 Project Report 总被引:1,自引:1,他引:0
K.L. Kwok 《Information Retrieval》2000,3(4):313-338
Both English and Chinese ad-hoc information retrieval were investigated in this Tipster 3 project. Part of our objectives is to study the use of various term level and phrasal level evidence to improve retrieval accuracy. For short queries, we studied five term level techniques that together can lead to good improvements over standard ad-hoc 2-stage retrieval for TREC5-8 experiments. For long queries, we studied the use of linguistic phrases to re-rank retrieval lists. Its effect is small but consistently positive.For Chinese IR, we investigated three simple representations for documents and queries: short-words, bigrams and characters. Both approximate short-word segmentation or bigrams, augmented with characters, give highly effective results. Accurate word segmentation appears not crucial for overall result of a query set. Character indexing by itself is not competitive. Additional improvements may be obtained using collection enrichment and combination of retrieval lists.Our PIRCS document-focused retrieval is also shown to have similarity with a simple language model approach to IR. 相似文献
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论第四种情报检索语言系统 总被引:7,自引:0,他引:7
第四种情报检索语言是自然语言与人工语言结合的一体化语言。第四种情报检索语言系统是一种基于网络的信息检索系统 ,比分类主题一体化情报检索语言系统更高级更新颖 ,是我国 2 1世纪情报检索语言系统研究的方向。加快我国第四种情报检索语言系统研究的关键 ,是解决汉语分词技术问题。参考文献 14。 相似文献
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单汉字标引方法的改进研究 总被引:2,自引:1,他引:1
本文根据信息论中的交互信息,给出了相邻汉字相关度的测量方法,在此基础上提出了基于字串预分割的单汉字标引检索方法,对当前具有代表性的单汉字标引方法进行了改进研究。试验证明本文提出的方法具有较好的性能 相似文献
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中文全文检索技术的研究及实现 总被引:9,自引:0,他引:9
本文设计了一个中文全文检索系统 ,在单汉字全文数据库的基础之上进行了全文检索的算法研究 ,提出了针对特定检索策略的计算公式。同时还对检索结果集的排序问题进行了讨论 ,并采用用户反馈信息量 ,使最后检出的结果在应用中不断得到优化 相似文献