AUC of prediction results using different co-tag features within t early hours.

† A linear combination with coefficients determined by regression fitting using least squared error.Prediction features include the number of tweets containing the co-tags (T), the number of co-tag adopters (A), the diversity of co-tags (H2), and the number of observed co-tags (m). The threshold is expressed as a top percentile of most popular hashtags that are deemed viral for evaluation purposes. Best results for each column are bolded.