A Time-Series Analysis of Public Diplomacy Expenditure and News Sentiment: A Case Study of the US-Japan Relationship

This study tested a lagged correlation between Japanese public diplomacy expenditure in the United States and U.S. news sentiment about Japan from 1996 to 2018. We conducted a sentiment analysis to measure news sentiment of The New York Times, The Washington Post, and The Wall Street Journal for 45,822 news articles with 30,197 unique bigram tokens. Using a time-series analysis, this study found that Japanese public diplomacy expenditure was positively related to U.S. news sentiment after controlling for Japanese exports to the U.S. and Japanese real GDP. In our test for the opposite direction, U.S. news sentiment was also positively associated with public diplomacy expenditure, after controlling for Japanese exports to the U.S. and Japanese real GDP.