Aspect-Based Sentiment Analysis of Nepali Text Using BERT Based Model
摘要
Aspect-based sentiment analysis (ABSA) is a fine-grained sentiment analysis which aims in extracting opinion terms, opinion targets, aspect category and the polarity associated with each aspect category. Most ABSA research is in English with minimal work in Nepali. We have added 1031 Nepali comments related to news and politics category from YouTube to the dataset by previous researcher under same annotation guideline to facilitate the research of ABSA in social media domain. This paper introduces target-oriented opinion term extraction (TOWE) in Nepali ABSA, alongside aspect category detection (ACD) and aspect category polarity (ACP) detection tasks. We present convincing results using NepaliBERT for TOWE with ROUGE-L score of 0.80. We experiment with various models including SVM, LSTM, BiLSTM, CNN, and multilingual BERT for ACD and aspect category polarity achieving F1-scores of 82.78% and 83.13% for ACD and ACP respectively. Our method has outperformed current State-of-the-art for classification tasks in Nepali.