Assessment of online public opinions on large infrastructure projects: A case study of the Three Gorges Project in China

• We developed a framework to assess online public opinion on large infrastructure projects with environmental impacts.
• Indicators were built to assess post intensity, sentiment polarity and major topics of the public opinion.
• We took the Three Gorges Project (TGP) as an example to demonstrate the effectiveness proposed framework.
• We revealed spatial-temporal patterns of post intensity and sentiment polarity on the TGP.
• We drew implications for a more in-depth understanding of the public opinion on large infrastructure projects.

Public opinion becomes increasingly salient in the ex post evaluation stage of large infrastructure projects which have significant impacts to the environment and the society. However, traditional survey methods are inefficient in collection and assessment of the public opinion due to its large quantity and diversity. Recently, Social media platforms provide a rich data source for monitoring and assessing the public opinion on controversial infrastructure projects. This paper proposes an assessment framework to transform unstructured online public opinions on large infrastructure projects into sentimental and topical indicators for enhancing practices of ex post evaluation and public participation. The framework uses web crawlers to collect online comments related to a large infrastructure project and employs two natural language processing technologies, including sentiment analysis and topic modeling, with spatio-temporal analysis, to transform these comments into indicators for assessing online public opinion on the project. Based on the framework, we investigate the online public opinion of the Three Gorges Project on China's largest microblogging site, namely, Weibo. Assessment results present spatial-temporal distributions of post intensity and sentiment polarity, reveals major topics with different sentiments and summarizes managerial implications, for ex post evaluation of the world's largest hydropower project. The proposed assessment framework is expected to be widely applied as a methodological strategy to assess public opinion in the ex post evaluation stage of large infrastructure projects.