【摘要】 本文综述了基于信源信道思想和基于最大熵思想的统计机器翻译方法并介绍了统计机器翻译的评测方法。基于信源信道的方法将翻译概率表示为一个语言模型和一个翻译模型。而基于最大熵的方法则是利用一系列实数值特征函数的线性组合来求解最优的译文。基于最大熵的统计机器翻译方法比基于信源信道的方法更具有一般性 ,后者可以看做前者的一个特例。更多还原

【Abstract】 The paper gives a survey on three approaches of statistical machine translation and the evaluation methods used in SMT. The basic idea of parallel grammar based approach is to build parallel grammars for source and target languages, which conform the same probabilistic distribution. In the source-channel approach, the translation probability is expressed as a language model and a translation model. In the maximum entropy approach, the optimal translation is searched according to a linear combination of a series of real-valued feature functions. The source-channel approach can be regard as a special case of maximum entropy approach.更多还原