Newspapers tone and the overnight-intraday stock return anomaly

We examine the associations between newspapers tone and stock market indices by translating newspapers coverage into human sentiment gauge. Our tone has positive effects on overnight stock returns and negative effects on both intraday returns and conditional volatility. The positive effect of the tone is highly significant on days of sharp price declines and when the tone is calculated using general newspapers. That positive effect, apparently thru opening prices, partly explains the overnight-intraday anomaly. The impact of negative events' coverage is about double the impact of positive events’ coverage. This asymmetry is greater when distinguishing between general and business newspapers.