长尾查询搜索性能评价方法的研究

各大搜索引擎公司都致力于准确而快速的帮助用户找到信息目标,搜索性能评价变得非常重要,而目前尚无对长尾查询性能评价的方法。该文通过分析长尾查询结果数据,提取了长尾查询三种类型特征,并对特征进行叠加分析。进一步地针对数据集的严重不平衡问题提出两种数据平衡方法。最后提出并改进了长尾查询评价方法。在真实搜索引擎结果数据集上的实验验证了所提出的评价方法取得一定的评价效果,其中对不相关文档的评价取得较高的准确率。     

基于分类评价的元搜索引擎调度策略

元搜索引擎的调度策略研究如何选择贴近需求的成员搜索引擎组合,以较小的资源耗费,帮助用户获得较高的查询质量.提出了一种基于检索术语分类的评价方法,根据成员搜索引擎的查全率、查准率和平均响应时间,量化其查询性能,然后根据评分高低,为每个分类的查询请求分配合适的成员搜索引擎组合.为该调度策略设计了实验系统,并对实验结果进行了分析与对比,结果表明,该调度策略有效地提高了查准率.     

一种基于查询特性的查询结果缓存与预取方法

针对搜索引擎查询结果缓存与预取问题,该文提出了一种基于查询特性的搜索引擎查询结果缓存与预取方法,该方法包括用来指导预取的查询结果页码预测模型和缓存与预取算法框架,用于提高搜索引擎系统性能。通过对国内某著名中文商业搜索引擎的某段时间的用户查询日志分析得出,用户对不同查询返回的查询结果所浏览的页数具有显著的非均衡性,结合该特性设计查询结果页码预测模型来进行预取和分区缓存。在该搜索引擎两个月的大规模真实用户查询日志上的实验结果表明,与传统的方法相比,该方法可以获得3.5%~8.45%的缓存命中率提升。     

信息检索中支持结果多样化的查询性能预测

对支持检索结果多样化任务的查询性能预测进行了研究。分析了现有性能预测算法的不足,考虑利用不同方式衡量最终检索结果列表的多样性,并在此基础上提出同时考察查询结果的相关性性能与多样性性能的三种方法。采用TREC Clue Web09B数据集、Web Track任务的查询集及开源的Indri搜索引擎构建实验平台并进行实验。基于Spearman、Pearson和Kendall相关系数的评价结果表明,所提出的三种方法与传统方法相比更适用于预测多样化检索结果,且在不同条件下性能稳定。     

基于后向链接的查询路由研究

尽管通用搜索引擎已经被广泛使用，但它们筛选用户查询结果中无关结果的功能一直不能任人满意，因此有些搜索需要使用专题搜索引擎，文章提出了一种基于中文专题搜索引擎的查询路由架构，该架构为用户的查询寻找合适的专题搜索引擎路由，并找出最佳搜索引擎，除了描述构架外，其中使用到的查询扩展和聚类算法文章也一并给出。     

基于用户特性的搜索引擎查询结果缓存与预取

针对搜索引擎查询结果缓存与预取问题,与传统的基于查询特性相关的方法不同,提出了一种基于用户特性的缓存与预取方法,用于提高搜索引擎系统性能,尤其针对部分用户效果更显著。通过对国内某著名商业搜索引擎用户的查询贡献分析得出,用户对搜索引擎的贡献具有长尾分布特性,结合该特性设计查询结果预测模型来进行预取和分区缓存。在该搜索引擎两个月的大规模真实用户查询日志上的实验结果表明,与传统的基于查询特性的典型方法相比,该方法可以获得3.03%~4.17%的命中率提升,对于查询贡献最大的0.25%的用户群体,可以获得20.52%~28.2%的命中率提升。     

搜索引擎的一种在线中文查询纠错方法

该文主要解决中文搜索引擎的查询纠错问题。错误的查询,已经偏离用户真实的搜索意图时,搜索质量很差,甚至导致搜索结果数为零。为此该文提出了一种服务于实际搜索引擎,较为完整的查询纠错方案。该文重点描述了纠错查询候选生成、纠错查询候选评价、以及基于核函数,挑选最优纠错查询候选等内容。通过在开放测试集上的准确率/召回率验证,以及在搜索引擎中实际的DCG评测,该文的方案都取得了较好的效果。     

基于日志分析的搜索引擎查询结果缓存研究

缓存是有效减少响应时间和系统负载的关键技术,是搜索引擎系统结构研究的重要领域之一.通过对搜狗搜索引擎在近1个月内约1500万条用户查询日志进行分析和研究,针对查询结果缓存,从查询局部性、缓存策略、缓存容量、工作负载周期性等方面进行分析.分析表明,混合缓存策略以及提高缓存容量相结合的技术能有效提高搜索引擎系统性能.     

利用查询修正系统提高搜索引擎性能的研究

针对原来的搜索引擎系统可能存在某些查询语意表达方面的错误,提出了利用查询修正系统来提高搜索引擎性能的方案,即在用户和Web站点之间增加一个查询修正系统,该系统可以解决由于查询用户自身知识或其他的原因造成的查询语意表达方面的错误,如查询术语错误、拼写错误、相关性问题等.     

一种基于预取感知接纳策略的查询结果缓存方法

针对搜索引擎查询结果缓存问题,提出了一种基于预取感知接纳策略的查询结果缓存方法,用于提高搜索引擎检索系统性能.查询结果预取导致查询结果页码的缓存缺失率具有显著差异性,结合该特性设计预取感知接纳策略,该策略包含查询评估模型以及模型特征选择方法.在该策略基础上,设计了一种查询结果缓存方法.在该搜索引擎两个月的大规模真实用户查询日志上的实验结果表明,与传统的典型方法相比,该方法可以获得6.38%～11.99%的缓存命中率提升.     

融合多类特征的Web查询意图识别

识别搜索引擎用户的查询意图在信息检索领域是备受关注的研究内容。文中提出一种融合多类特征识别Web查询意图的方法。将Web查询意图识别作为一个分类问题,并从不同类型的资源包括查询文本、搜索引擎返回内容及Web查询日志中抽取出有效的分类特征。在人工标注的真实Web查询语料上采用文中方法进行查询意图识别实验,实验结果显示文中采用的各类特征对于提高查询意图识别的效果皆有一定帮助,综合使用这些特征进行查询意图识别,88。5%的测试查询获得准确的意图识别结果。     

一种新的搜索引擎查询导向系统

网络上的专业搜索引擎数量众多，普通用户在选择时往往无所适从。文章提出了一个自动的查询导向系统，可以将用户查询自动导向到合适的专业搜索引擎，解决了这个矛盾。     

元搜索中成员搜索引擎的选择问题研究

随着网络的普及,网上检索成为了人们获取信息的主要方式。目前的搜索引擎相对独立,覆盖范围比较有限。相比之下,元搜索能够更好地满足用户的检索需求。当用户在元搜索提供的统一界面中输入一个查询时,元搜索会将处理后的用户请求发送给相关的成员搜索引擎。但是一个重要的问题是如何识别出潜在的搜索引擎以便更好地处理用户的请求。鉴于此提出了一种基于遗传算法的选择机制,该方法将各个成员搜索引擎的权重考虑在内。实验结果表明,该方法确实能够提高引擎选择中的效率和精度。     

Mining search engine query logs for social filtering-based query recommendation

This paper presents a simple and intuitive method for mining search engine query logs for fast social filtering, where searchers are provided with dynamic query recommendations on a large-scale industrial-strength search engine. We adopt a dynamic approach that is able to absorb new and recent trends in web usage trends on search engines, while forgetting outdated trends, thus adapting to dynamic changes in web user’s interests. In order to get well-rounded recommendations, we combine two methods: first, we model search engine users’ sequential search behavior, and interpret this consecutive search behavior as client-side query refinement, that should form the basis for the search engine’s own query refinement process. This query refinement process is exploited to learn useful information that helps generate related queries. Second, we combine this method with a traditional text or content based similarity method to compensate for the shortness of query sessions and sparsity of real query log data.     

Implementing and evaluating phrasal query suggestions for proximity search

This paper describes and evaluates a unified approach to phrasal query suggestions in the context of a high-precision search engine. The search engine performs ranked extended-Boolean searches with the proximity operator near being the default operation. Suggestions are offered to the searcher when the length of the result list falls outside predefined bounds. If the list is too long, the engine specializes the query through the use of super phrases; if the list is too short, the engine generalizes the query through the use of proximal subphrases.We describe methods for generating both types of suggestions and present algorithms for ranking the suggestions. Specifically, we present the problem of counting proximal subphrases for specialization and the problem of counting unordered super phrases for generalization.The uptake of our approach was evaluated by analyzing search log data from before and after the suggestion feature was added to a commercial version of the search engine. We looked at approximately 1.5 million queries and found that, after they were added, suggestions represented nearly 30% of the total queries. Efficacy was evaluated through a controlled study of 24 participants performing nine searches using three different search engines. We found that the engine with phrasal query suggestions had better high-precision recall than both the same search engine without suggestions and a search engine with a similar interface but using an Okapi BM25 ranking algorithm.     

An analysis of web proxy logs with query distribution pattern approach for search engines

This study presents an analysis of users' queries directed at different search engines to investigate trends and suggest better search engine capabilities. The query distribution among search engines that includes spawning of queries, number of terms per query and query lengths is discussed to highlight the principal factors affecting a user's choice of search engines and evaluate the reasons of varying the length of queries. The results could be used to develop long to short term business plans for search engine service providers to determine whether or not to opt for more focused topic specific search offerings to gain better market share.     

LESSON: A system for lecture notes searching and sharing over Internet

In this paper, we present a system LESSON for lecture notes searching and sharing, which is dedicated to both instructors and students for effectively supporting their Web-based teaching and learning activities. The LESSON system employs a metasearch engine for lecture notes searching from Web and a peer-to-peer (P2P) overlay network for lecture notes sharing among the users. A metasearch engine provides an unified access to multiple existing component search engines and has better performance than general-purpose search engines. With the help of a P2P overlay network, all computers used by instructors and students can be connected into a virtual society over the Internet and communicate directly with each other for lecture notes sharing, without any centralized server and manipulation. In order to merge results from multiple component search engines into a single ranked list, we design the RSF strategy that takes rank, similarity and features of lecture notes into account. To implement query routing decision for effectively supporting lecture notes sharing, we propose a novel query routing mechanism. Experimental results indicate that the LESSON system has better performance in lecture notes searching from Web than some popular general-purpose search engines and some existing metasearch schemes; while processing queries within the system, it outperforms some typical routing methods. Concretely, it can achieve relatively high query hit rate with low bandwidth consumption in different types of network topologies.