Tibetan Syntax Analysis Based On PCFG

The study of words and words in the field of Tibetan natural language processing has achieved good research results,and syntactic analysis is still in its infancy.Syntactic analysis is an important basic work that plays a decisive role in all fields.It is also the basis for a deep understanding of Tibetan language.The results will affect many aspects of natural language processing problems in terms of accuracy and recall rate.Therefore,syntactic analysis has important theoretical significance and application value in Tibetan natural language processing.This dissertation analyzes and studies Tibetan Sentences from the following aspects:(1)Tibetan sentence extraction techniqueBy analyzing the distribution characteristics of the tail-sentences in the Tibetan sentence clauses,we can determine the part of speech that can appear at the end of the Tibetan sentence,and propose a method of extracting Tibetan sentences by retrogressive action words,which improves the efficiency of Tibetan sentence extraction.Experiments show that using sentence retrieval method of retrospective virtual words can extract ideal sentences.(2)Classification and formal description of Tibetan phrasesAccording to the grammatical functions,Tibetan phrases are divided into 8 categories,namely noun phrases,verb phrases,adjective phrases,pronodic phrases,adverbial phrases,temporal part-of-speech phrases,adverbial phrases,and numerallike phrases.The formal description of Tibetan phrases was given,feature templates were given,and structural components were analyzed.(3)Analysis of Tibetan SentencesThe PCFG method was used to train the Tibetan sentence analysis model.The probabilistic CYK algorithm was used to decode the syntax,and the ambiguous sentences were disambiguated by calculating the total probability of the grammar of the sentence.Experiments show that the PCFG-based Tibetan sentence analysis has got good results.The accuracy of the open test results was 91.5%,the recall rate was 88.5%,the F value was 91.5%,the accuracy of the closure test experiment was 94.7%,the recall rate was 91.8%,and the F value was 93.2%.