Sentiment analysis has been widely used in text mining of social media to discover valuable information from user reviews. Sentiment lexicon is an essential tool for sentiment analysis. Recent research studies indicate that constructing sentiment lexicons for special domains can achieve better results in sentiment analysis. However, it is not easy to construct a sentiment lexicon for a specific domain because most current methods highly depend on general sentiment lexicons and complex linguistic rules. In this paper, the construction of sentiment (...) lexicon is transformed into a training-optimization process. In our scheme, the accuracy of sentiment classification is used as the optimization objective. The candidate sentiment lexicons are regarded as the individuals that need to be optimized. Then, two genetic algorithms are specially designed to adjust the values of sentiment words in lexicon. Finally, the best individual evolved in the presented genetic algorithms is selected as the sentiment lexicon. Our method only depends on some labelled texts and does not need any linguistic knowledge or prior knowledge. It provides a simple and easy way to construct a sentiment lexicon in a specific domain. Experiment results show that the proposed method has good flexibility and can generate high-quality sentiment lexicon in specific domains. (shrink)

An equal and high-quality partnership between public and private sectors is essential to the sustainable development of public–private partnership projects. However, in the special social circumstance in China, the public sector has a strong voice in PPP projects. According to the existing research on PPP project failure, the government's dishonest performance and negative cooperative attitude and the private sector's speculative behavior of concealing information will lead to termination or even failure of project. The attitude and behavior that reflect the relationship (...) orientation of public sector may determine whether the private sector adopts an opportunistic behavior. However, few studies have revealed the mechanism of relationship orientation on opportunism in PPP projects. This paper proposes the connotation of the public sector's relationship orientation and designs a measurement scale from three aspects: emotional relationship orientation, instrumental relationship orientation, and rent-seeking relationship orientation. Based on the data from large construction enterprises, financial institutions and investors, and scholars with practical experience in PPP projects, this paper explores the mechanism of the public sector's relationship orientation on the private sector's justice perception and opportunistic behavior by using the structural equation model. The results show that the public sector's relationship orientation significantly affects the formation and development of the private sector's justice perception and opportunistic behavior, justice perception plays a mediating role in the process of relationship orientation acting on opportunistic behavior, and the instrumental relationship orientation is more conducive to reducing the opportunistic behavior. The results provide new ideas for changing the public sector's concept and attitude and regulating behavior in PPP projects. (shrink)