IEST: WASSA-2018 Implicit Emotions Shared Task
Table 2: Distribution of IEST data.
['Emotion', 'Train', 'Trial', 'Test']
The initially retrieved large dataset has a distribution of 25 % surprise, 23 % sadness, 18 % joy, 16 % fear, 10 % anger, 8 % disgust. We discard tweets with more than one emotion word, as well as exact duplicates, and mask usernames and URLs. From this set, we randomly sample 80 % of the tweets to form the training set (153,600 instances), 5 % as trial set (9,600 instances), and 15 % as test set (28,800 instances). We perform stratified sampling to obtain a balanced dataset. While the shared task took place, two errors in the data preprocessing were discovered by participants (the use of the word unhappy as synonym for sadness, which lead to inconsistent preprocessing in the context of negated expressions, and the occurrence of instances without emotion words).