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arXiv cs/0110027cs.CL
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基于两个连续变换器的词性标注

Part-of-Speech Tagging with Two Sequential Transducers

Andre Kempe

摘要:

我们提出了一种方法,构建和使用级联组成的左和右顺序有限状态传感器(FST),T1和T2,部分的语音(POS)消歧。与HMM相比,这种FST级联具有显著更高的处理速度的优点,但代价是精度略低。像信息检索这样的应用程序,速度可能比准确性更重要,可以从这种方法中受益。在标注过程中,我们首先为每个词分配一个唯一的歧义类c_i,该歧义类可以在由顺序FST编码的词典中查找。每个c_i都由一个符号表示,例如[ADJ_NOUN],尽管它表示一组给定单词可以出现的替代标记。一个句子中所有单词的c_i序列是我们FST级联的输入。它由T1从左到右映射到一系列简化的模糊度类r_i。每个r_i由单个符号表示,尽管它表示一组可选标记。直观地,T1从c_i中消除了不太可能的标签,从而创建了r_i。最后,T2将r_i的序列从右到左映射到单个POS标签的序列t_i。直观地,T2从每个r_i中选择最可能的t_i。所有t_i、r_i和c_i的概率仅在编译时使用,而不在运行时间使用。它们并不(直接)出现在FST中,而是“隐含地包含”在它们的结构中。

英文摘要:

We present a method of constructing and using a cascade consisting of a left- and a right-sequential finite-state transducer (FST), T1 and T2, for part-of-speech (POS) disambiguation. Compared to an HMM, this FST cascade has the advantage of significantly higher processing speed, but at the cost of slightly lower accuracy. Applications such as Information Retrieval, where the speed can be more important than accuracy, could benefit from this approach. In the process of tagging, we first assign every word a unique ambiguity class c_i that can be looked up in a lexicon encoded by a sequential FST. Every c_i is denoted by a single symbol, e.g. [ADJ_NOUN], although it represents a set of alternative tags that a given word can occur with. The sequence of the c_i of all words of one sentence is the input to our FST cascade. It is mapped by T1, from left to right, to a sequence of reduced ambiguity classes r_i. Every r_i is denoted by a single symbol, although it represents a set of alternative tags. Intuitively, T1 eliminates the less likely tags from c_i, thus creating r_i. Finally, T2 maps the sequence of r_i, from right to left, to a sequence of single POS tags t_i. Intuitively, T2 selects the most likely t_i from every r_i. The probabilities of all t_i, r_i, and c_i are used only at compile time, not at run time. They do not (directly) occur in the FSTs, but are "implicitly contained" in their structure.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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