ISCAS participated in two subtasks of SemEval 2020 Task 5: detecting counterfactual statements and detecting antecedent and consequence. This paper describes our system which is based on pre-trained transformers. For the first subtask, we train several transformer-based classifiers for detecting counterfactual statements. For the second subtask, we formulate antecedent and consequence extraction as a query-based question answering problem. The two subsystems both achieved third place in the evaluation. Our system is openly released at https://github.com/casnlu/ISCAS-SemEval2020Task5.
@article{arxiv.2009.08171,
title = {ISCAS at SemEval-2020 Task 5: Pre-trained Transformers for Counterfactual Statement Modeling},
author = {Yaojie Lu and Annan Li and Hongyu Lin and Xianpei Han and Le Sun},
journal= {arXiv preprint arXiv:2009.08171},
year = {2020}
}