The ComOM shared task aims to extract comparative opinions from product reviews in Vietnamese language. There are two sub-tasks, including (1) Comparative Sentence Identification (CSI) and (2) Comparative Element Extraction (CEE). The first task is to identify whether the input is a comparative review, and the purpose of the second task is to extract the quintuplets mentioned in the comparative review. To address this task, our team proposes a two-stage system based on fine-tuning a BERTology model for the CSI task and unified multi-task instruction tuning for the CEE task. Besides, we apply the simple data augmentation technique to increase the size of the dataset for training our model in the second stage. Experimental results show that our approach outperforms the other competitors and has achieved the top score on the official private test.

翻译：ComOM共享任务旨在从越南语产品评论中提取比较性观点。该任务包含两个子任务：(1)比较句识别（CSI）和(2)比较元素抽取（CEE）。第一个任务是判断输入是否为比较性评论，第二个任务旨在提取比较性评论中提到的五元组。为解决该任务，我们的团队提出了一种两阶段系统：针对CSI任务采用基于BERTology模型的微调方法，针对CEE任务采用统一多任务指令微调方法。此外，我们在第二阶段应用简单数据增强技术以扩大训练数据集规模。实验结果表明，我们的方法优于其他参赛者，并在官方私有测试集上取得了最高分数。