“…Recently, the role of market news sentiment, in particular machine-driven sentiment signals, and their implication for financial market processes, has captured the attention of both investment practitioners and academics. There is a growing body of research that argues that news items from different sources influence investor sentiment, and hence asset prices, asset price volatility and risk (Tetlock, 2007;Tetlock et al, 2008;Da et al, 2011;Barber and Odean, 2008;diBartolomeo and Warrick, 2005a;Mitra et al, 2008;Dzielinski et al, 2011). Bhattacharya et al (2009) explore news items that came out between 1996 and 2000 on 458 Internet initial public offerings (IPOs) and a matching sample of 458 non-Internet IPOs (a total of 171,488 news items).…”