【摘 要】
：
在信息检索过程中,因查询词短少而引起的检索歧义性是影响检索效率的主要原因之一,而查询扩展方法和本体扩展方法能有效改善这一问题.提出一种基于本体和局部上下文分析的查
论文部分内容阅读
在信息检索过程中,因查询词短少而引起的检索歧义性是影响检索效率的主要原因之一,而查询扩展方法和本体扩展方法能有效改善这一问题.提出一种基于本体和局部上下文分析的查询扩展方法:本体扩展根据本体推理规则对短查询词进行推理,得到与查询词有逻辑关联的推理结果集,为查询词加入了标准化的关联信息.局部上下文分析通过对文档库的分析,在与用户查询词最相关的前m篇文档中抽取与用户查询词最相关的n个扩展词,为查询词加入了统计扩展信息.将两部分扩展查询词合并,再通过扩展查询词相关度计算对搜索结果集进行排序.该方法结合了这两种方法的各自优势,从语义角度扩展关键词.实验分析表明,该方法能有效提高检索查全率和查准率.
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