Are National Newspapers Polarizing?-A Quantitative Text Analysis Approach

2023 Fiscal Year Final Research Report

• Project/Area Number: 19K13607
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 06010:Politics-related
• Research Institution: Waseda University
• Principal Investigator: Hosogai Ryo 早稲田大学, 政治経済学術院, その他(招聘研究員) (30582259)
• Project Period (FY): 2019-04-01 – 2024-03-31
• Keywords: 極性化 / テキスト分析 / 内容分析 / 新聞

Outline of Final Research Achievements

This study is intended to approach polarization in national newspapers, which has been noted to be progressing in recent years, using a method of text analysis. Using supervised machine learning method, I proposed the Polarization Index, which measures the degree of text polarization, and applied it to articles in four national newspapers. The results showed that the tone of the four newspapers was in line with the conventional view of "liberal Asahi/Mainichi" versus "conservative Yomiuri/Sankei," but these differences were not large, and there was no evidence of polarization in the national newspaper text.

Free Research Field

政治学

Academic Significance and Societal Importance of the Research Achievements

政治的言論の多様性と相互の交流は民主主義において不可欠なものとされているが、近年、政治的な言論空間の「分極化」や「分断化」が指摘されることが多くなった。この文脈で、日本における言論の大きな担い手である全国新聞の論調もまた極性化していると指摘されることが多かったが、本研究では計量テキスト分析手法を用いて実証的にこの問題にアプローチした。本研究の知見は、全国新聞の極性化について実証的な基盤を与えると同時に、言論空間の「分断化」をめぐる近年の社会的な議論にも示唆をもたらすと考えられる。