Analysis On Sentiment Orientation And Its Evolution Of Emergency Network Public Opinion

Since emergency owns the characteristics of uncertainty, wide impact and seriousconsequence, emergency becomes the focus of public attention. With the widespread ofonline communication platform, like forums and micro-blogs, network public opinionon emergency forms soon and spreads fast. Based on the analysis on public opinion, wecan understand public attitudes and figure out the insufficient of emergency responseand handling work, which turns to be the basis of work improvement anddecision-making in the future.Generally, the comment objects of emergency network public opinion include notonly the event but also the government, media, etc. For different comment objects, thesentiment words used by the public may differ and the evolution of network publicopinion may have different characteristics. Hence, the sentiment analyses and theevolution analyses of public opinion need to be performed respectively by differentobjects.As to analyze the sentiment orientation and its evolution of public opinion onemergency, this paper, in the first place, collects data from Tianya By-talk of TianyaForum and clusters the comments into four categories by using text clustering. Thecategories are government department, media, the cause and others. Then, this paperanalyzes the sentiment orientation of online reviews based on a sentiment lexicon whichis built with sentiment words provided by HowNet. From the experiment results withdifferent feature extraction methods and text classification methods, it indicates that theprecision of information gain and SVM is higher than others. Based on sentimentanalysis, this paper analyzes the evolutions of network public opinion in differentcategories. The evolution analysis aligning with hot topics shows that the topics havecontributed to explain the reason of emotional changes. By analysis on the relationshipbetween positive commentators’ opinion and public opinion, I find that positivecommentators have an emotional guidance effect on negative emotion of public opinionin the reviews of government department class.