The Media and the Diffusion of Information in Financial Markets: Evidence from Newspaper Strikes
研究了报纸罢工对交易量和价格波动的影响，发现媒体通过传播信息提升股市效率，对投资者和监管者理解信息扩散机制有参考价值。
ABSTRACT The media are increasingly recognized as key players in financial markets. I investigate their causal impact on trading and price formation by examining national newspaper strikes in several countries. Trading volume falls 12% on strike days. The dispersion of stock returns and their intraday volatility are reduced by 7%, while aggregate returns are unaffected. Moreover, analysis of return predictability indicates that newspapers propagate news from the previous day. These findings demonstrate that the media contribute to the efficiency of the stock market by improving the dissemination of information among investors and its incorporation into stock prices.