  Stock prices are driven by various factors. In particular, many individual
investors who have relatively little financial knowledge rely heavily on the
information from news stories when making investment decisions in the stock
market. However, these stories may not reflect future stock prices because of
the subjectivity in the news; stock prices may instead affect the news
contents. This study aims to discover whether it is news or stock prices that
have a greater impact on the other. To achieve this, we analyze the
relationship between news sentiment and stock prices based on time series
analysis using five different classification models. Our experimental results
show that stock prices have a bigger impact on the news contents than news does
on stock prices.
