Task: Determine the prevailing emotional tone of the tweet, categorizing it as either 'neutral or no emotion' or as one or more of the given emotions (anger, anticipation, disgust, fear, joy, love, optimism, pessimism, sadness, surprise, trust) that most accurately represent the tweeter's mental state.
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