关键词: 舆情, 话题倾向性, 情感词汇Ontology

Abstract: In allusion to the unlighted public opinion information，the important aspects of public opinion analysis are as follows：network hot spots，focus and sensitive topic mining，public opinion trends control，the ability to handle and monitor the network emergency improvement and so on.Topic semantic orientation compute based on sentiment words ontology is studied.The orientation weights of the words are calculated by calculating the semantic similarity of the words in sentiment words ontology and counting the sentiment words frequencies in the topic corpus.Then the topic orientation extent and the overall orientation can be calculated according to the orientation weights of the words.Finally，the sentiment classification and orientation extent of each corpus in the topic is tagged by the fine-grained standard based on sentiment words ontology.

Key words: public opinion, topic orientation, sentiment words Ontology