Attention-based semi-supervised active learning for multi-class tweet classification
摘要
This paper presents a transformer-based semi-supervised active learning framework for tweet categorization. We focus on distinguishing information, emotion, neutral, and irrelevant tweets in case of a crisis. For this work, we considered the event “Fall of Kabul". We introduce a frequency-based sampling algorithm that deals with the temporal variations in tweet frequency for selecting tweets for initial manual annotation. A pre-trained BERT model is utilized for the classification of labelled data. As part of our iterative active learning process, we select representative tweets from the unlabelled pool. We manually annotate tweets with low-confidence scores and assign pseudo-labels to others. These labelled tweets are used to retrain the model over successive iterations. By using active learning, our approach makes full use of both supervised and unsupervised learning with reduced labelling costs while maintaining satisfactory model performance. We present the class-wise performance of the model and show that our model is able to achieve 0.806 accuracy and is effective in identifying the four classes successfully for the crisis with satisfactory F1-scores.