When politics intervenein non-political news flow: Trans-regional intermedia agenda-settingbetween Mainland China, Hong Kong,and Taiwan on online air pollution news

Abstract While intermedia agenda-setting scholars have examined the process from a global perspective, trans-regional intermedia agenda setting, especially in non-western context, remains understudied. By analyzing the time-series data of news coverage on air pollution, a non-political topic, from online news media in mainland China, Hong Kong, and Taiwan from 2015 to 2018, this study revealed a triangular first-level agenda-setting relationship among the three regions and identified the changing agenda setters across years, which disproves the imperialistic stereotype that there is a one-way control from mainland China media. The study also revealed the significant yet unconventional moderating effect of the political stance of news organizations in the trans-regional information flow. This study contributes to the intermedia agenda-setting literature by introducing the method of controlling the real-life situation in the Granger Causality test and by showing that non-political issues can also be politicalized in the salience transferring process.