搜索引擎搜索结果的评价技术

搜索引擎根据用户查询在自己的索引数据库中进行查找，并根据相关性分析将查询结果返回给用户。本文就传统信息检索系统的性能效率评价技术,针对Internet的特点，对搜索引擎搜索结果的评价进行了讨论。     

OPAC拼音搜索功能的设计与实现

针对当前汉字输入不便而造成OPAC检索效率低下的现状,进行拼音搜索的研究。对书目数据和用户检索行为进行收集、利用、挖掘和整理,以此构建动态汉字拼音数据库,实现基于AJAX的拼音输入提示、基于ASP的拼音搜索提示以及直接拼音搜索功能,对用户的检索行为给出检索建议,以期简化输入、提升检索体验。     

学术新人的信息行为研究

本文以三年级本科生为研究对象,通过给学生布置难度较大的课程论文,然后要求学生详细记录信息检索过程中的检索策略、检索过程、检索结果及思考。基于文本数据,采用内容分析法分析了实验对象的数据库、检索字段、排序方式以及限定条件的选择、检索结果记录数与二次检索的关系、检索式的构建中的用户行为。论文提炼了学生的检索模式,分别为文献计量模式、参考文献模式、核心期刊模式、搜索引擎模式、渐进模式以及常规模式。     

数字环境下文献分类法的检索应用及其发展

在数字环境下,文献分类检索应以等级浏览形式为主,重视易用性、灵活性,同时进行必要的多维化改造、完善相关关系揭示等。数字化环境下的应用必然给类表带来结构上的变化,需要进行相应技术探索,并应根据其在检索体系中的定位,研讨应用规律。另外,表达了对检索软件编制的一些看法。     

相似检索与链接检索的性能评价研究

Google为用户提供了多种检索功能,但这些检索功能的性能如何却少见于相关文献中。作者对Google的两种较为独特的检索功能进行了评析,分别是相似检索和链接检索,并以普通检索作为评价的标准。本文采用了20个检索式和20个目标网页,对相似检索、链接检索和普通检索的检索性能差异性进行了评价。研究中主要利用单因素方差分析法和回归分析法。研究结果显示普通检索表现最好。研究成果能帮助用户对相似检索和链接检索有较为清晰的认识,并且可以了解Google在这两种检索功能上所表现出的不同的检索性能。     

基于WEB的全文搜索引擎系统设计与实现

随着企事业单位信息资源的膨胀,如何优化企事业信息资源检索越发重要。从分析开源搜索引擎lucene出发,设计了一种基于SSlweb框架和lucene全文搜索工具包的全文搜索引擎系统,实现了以B／S模式远程搜索服务器文件,满足局域网内对文档搜索的需求,实验结果表明该搜索引擎有效地提高信息检索的准确度。     

Information retrieval in the workplace: A comparison of professional search practices

Legal researchers, recruitment professionals, healthcare information professionals, and patent analysts all undertake work tasks where search forms a core part of their duties. In these instances, the search task is often complex and time-consuming and requires specialist expertise to identify relevant documents and insights within large domain-specific repositories and collections. Several studies have been made investigating the search practices of professionals such as these, but few have attempted to directly compare their professional practices and so it remains unclear to what extent insights and approaches from one domain can be applied to another. In this paper we describe the results of a survey of a purposive sample of 108 legal researchers, 64 recruitment professionals and 107 healthcare information professionals. Their responses are compared with results from a previous survey of 81 patent analysts. The survey investigated their search practices and preferences, the types of functionality they value, and their requirements for future information retrieval systems. The results reveal that these professions share many fundamental needs and face similar challenges. In particular a continuing preference to formulate queries as Boolean expressions, the need to manage, organise and re-use search strategies and results and an ambivalence toward the use of relevance ranking. The results stress the importance of recall and coverage for the healthcare and patent professionals, while precision and recency were more important to the legal and recruitment professionals. The results also highlight the need to ensure that search systems give confidence to the professional searcher and so trust, explainability and accountability remains a significant challenge when developing such systems. The findings suggest that translational research between the different areas could benefit professionals across domains.     

A knowledge-based semantic framework for query expansion

Searching for relevant material that satisfies the information need of a user, within a large document collection is a critical activity for web search engines. Query Expansion techniques are widely used by search engines for the disambiguation of user’s information need and for improving the information retrieval (IR) performance. Knowledge-based, corpus-based and relevance feedback, are the main QE techniques, that employ different approaches for expanding the user query with synonyms of the search terms (word synonymy) in order to bring more relevant documents and for filtering documents that contain search terms but with a different meaning (also known as word polysemy problem) than the user intended. This work, surveys existing query expansion techniques, highlights their strengths and limitations and introduces a new method that combines the power of knowledge-based or corpus-based techniques with that of relevance feedback. Experimental evaluation on three information retrieval benchmark datasets shows that the application of knowledge or corpus-based query expansion techniques on the results of the relevance feedback step improves the information retrieval performance, with knowledge-based techniques providing significantly better results than their simple relevance feedback alternatives in all sets.     

搜索引擎Google的检索功能及PageRank技术分析

本文介绍了搜索引擎Google的特点和检索功能，并重点介绍了其PageRank专利技术的概念及计算方法。     

中英文网络检索工具评价与比较

选用AltaVista 和搜狐两个网络检索工具, 利用10 个来自实际参考咨询的检索提问分别进行检索测试, 并根据由索引数据库构成、检索功能、检索效果、检索结果显示、用户负担五方面构成的评价标准, 进行具体评述和比较。由于无法估算网络中相关信息的总量, 所以文中忽略了查全率R 的计算, 但根据需要采用了重复率R r、死链接率Rd 两个新指标作为检索效果评价的标准。在上述评价的基础上, 分析中文检索工具存在的差距, 以及在选择评价标准时, 根据中、英文检索工具的特点, 应该有哪些不同。