Abstract

This paper examines the influence wielded by social media buzz on stock market performances of selected stocks from several ASEAN stock exchanges. The advent of social media has changed the dynamics of information propagation and utilization in stock markets. Though information asymmetry still persists, current literature has only recently caught up with the dominant trend of social media eclipsing traditional media as a source of information. This is an issue of significant complexity and import for stock market actors. Employing a brand-new theoretical model of predicting impact of social media on asset prices—proposed by Jiao, Veiga and Walther—this study gauges the performances of stocks with active social media coverage for a month and finds abnormally high trading volume and volatility in the ensuing month. Though these findings are statistically significant in confirming stale news hypothesis by Tetlock (2011), this study is the first empirical application of Jiao et al.’s model. Therefore, after discussing the implications of these findings, this paper highlights the need for more replication studies to help develop a social-media related theory on asset prices and how this affects regulators’ responsibility of ensuring fair dissemination of information.