Task: Categorize the tweet's emotional tone as either 'neutral or no emotion' or identify the presence of one or more of the given emotions (anger, anticipation, disgust, fear, joy, love, optimism, pessimism, sadness, surprise, trust).
Tweet: In inter-group relationships, #anger makes people think in more negative and prejudiced terms about outsiders.
This tweet contains emotions: 
anger, disgust, optimism, pessimism, sadness