基于文档结构的信息抽取规则的描述语言比较研究

Describe Languages' Comparing for Web Information Extraction Rules Based on Page Structure

基于文档结构的信息抽取工具很多 ,XWrap ,W 4F ,Lixto以及自主开发的PQagent是其中比较有代表性的几个 .这几个工具采用了不同的规则描述形式 ,XWrap ,W 4F ,Lixto使用的是自定义的规则描述形式 ,PQagent采用了通用的规范XQuery来描述规则 .现将XWrap ,W 4F ,Lixto使用的规则描述形式与PQagent采用的XQuery进行比较 ,说明了采用XQuery描述抽取规则的优越性 .

There are many information extraction tools based on structure.Among them,XWrap,W4F,Lixto and PQagent which is developed by ourself are pretty representative.Each one uses a different way to describe their extraction rules.XWrap,W4F and Lixto predefine different ways to describe their rules,as while PQagent using the universal criterion--XQuery.Here,XQuery is compared with the ways respectively used by XWrap,W4F and Lixto,and conclusion is drawn that there is more advantage to use XQuery.