Fig 4. Correlogram among the linguistic features.

These plots show correlations among linguistic features with significance for rumor events. Colors of circles represent correlation coefficients, where the dark blue (red) color indicates coefficients of 1 (-1). Size of circles represent the absolute values of correlation coefficients. Blank or no circle indicates non-significant cases where p-values ≥ 0.05. From (b), strong negation is expressed by a positive correlation between scores of ‘negation’ and ‘certain’. Interestingly, the ‘assent’ category increases for rumors, which indicates that users who confirmed the rumor also appeared as time passed.