Tzu-Yi Tang

• In the past few years, social media has become the most popular communication software, replacing phone calls, text messages, television and even advertisements. Social media has become the most important channel for spreading opinions. As a result of this trend, many politicians have also started to operate social media (Wang, Tsai, & Chen 2019). This study was conducted in order to understand whether there was an intercandidate agenda-setting effect between the Facebook posts of legislative candidates and presidential candidates during the election period, and whether the legislative candidates' Facebook posts were influenced by the presidential candidates' Facebook posts. The target population of this study was the three presidential candidates in Taiwan's 2020 presidential election — Dr. Tsai Ing-Wen, Mr. Han Kuo-Yu, and Mr. James Soong — as well as the 36 legislative candidates in Taipei, Taichung, and Kaohsiung. The study focused on Facebook posts from 1thNovember 2019 to 10th January 2020, 10 weeks before the voting day. Text-mining and cosine similarity were used to organize the posts and compare the similarity between posts. Finally, the similarity between posts was presented as a line graph. The study revealed that there was an inter-candidate agenda-setting effect between legislative candidate posts and presidential candidate posts, and that Dr. Tsai Ing-Wen, who was also the incumbent president during the campaign, was the most influential Facebook poster during the entire election. Future research is proposed on the inter-candidate agenda-setting effect only analyzing the similarity of posts among the candidates to discuss the influence of the candidates' Facebook agenda-setting during a specific election period. This is the first study in which the Facebook posts of Taiwanese politicians are analyzed and the relationships were analyzed and the relationships were systematically compared, across multiple degrees, which opens up a whole new subject for future elections in Taiwan.