FMI-SU at SemEval-2023 Task 7: Two-level Entailment Classification of Clinical Trials Enhanced by Contextual Data Augmentation
Sylvia Vassileva, Georgi Grazhdanski, Svetla Boytcheva, Ivan Koychev · 2023
The paper presents an approach for solving Se-mEval 2023 Task 7 -identifying the inference relation in a clinical trials dataset.The system has two levels for retrieving relevant clinical trial evidence for a statement and then classifying the inference relation based on the relevant sentences.In the first level, the system classifies the evidence-statement pairs as relevant or not using a BERT-based classifier and contextual data augmentation (subtask 2).Using the relevant parts of the clinical trial from the first level, the system uses an additional BERTbased classifier to determine whether the relation is entailment or contradiction (subtask 1).In both levels, the contextual data augmentation is showing a significant improvement in the F1 score on the test set of 3.7% for subtask 2 and 7.6% for subtask 1, achieving final F1 scores of 82.7% for subtask 2 and 64.4% for subtask 1.