2016美國總統大選中的政治極化與輿情分析：以臉書資料為例

Abstract

Facebook 及推特等社群軟體的崛起，讓社群媒體上的政治行為備受重視。本文則聚焦在2016美國總統大選中，Facebook上的政治極化現象與川普對於公眾輿論及議題設定的影響。本文使用Facebook上的使用者按讚資料，建立不同的意識形態極化指標來觀察Facebook上的政治極化程度，並進一步結合FBI的仇恨犯罪資料，探索對網路上的極化現象與現實世界中的犯罪行為間的關聯。此外，本文也試圖從Facebook資料中挖掘川普對於公眾輿論，特別是種族與移民議題上影響的證據。本文發現，Facebook上的政治極化程度確實隨著競選過程而提高，同時與仇恨犯罪行為間存在正相關。另外，資料顯示川普對於移民與種族議題的言論對於媒體的議題選擇造成部分影響，同時我們也發現保守派與自由派間對於相關議題的獲取行為存在差異，特別是在移民議題上。然而，沒有證據顯示川普在移民及種族議題上對閱聽者的態度及議題偏好有所影響。

Since social media platform such as Facebook and Twitter became popular among the world, the political behavior on social media has become a great interest of scholars. In this paper, we are interested in the level of political polarization and Trump's impact on public opinion and agenda setting on Facebook during 2016 U.S presidential campaign. We propose different indexes to observe the level of political polarization among users using an user-like data. In addition, combing with hate crime data from FBI, we explore the relationship between online polarization and offline hate crime behavior. We also seek for some evidence to show the impact of Donald Trump on public opinion toward immigration and racial issues on Facebook from our data. We find that the polarization level on Facebook did increase during the presidential campaign, with a positive correlation with hate crime numbers. Moreover, the data suggest that there are some impact of Trump on agenda building, and a polarization in attitudes toward our interested issues between conservatives and liberals, especially on immigration issues. However, there are no evidence showing that Trump has an impact on public attitude and first-level agenda setting.