PsuedoProp at SemEval-2020 Task 11: Propaganda Span Detection Using BERT-CRF and Ensemble Sentence Level Classifier
Aniruddha Chauhan, Harshita Diddee · 2020
This paper presents our solution for Span Identification (SI) Task under "Task 11: Detection of Propaganda Techniques in News Articles" of SemEval 2020.This task aims to identify if a given sentence, taken from a corpus of news articles, contains a propaganda span and hence aims to identify the character level offsets of the identified propaganda element.Our solution proposes a sequential approach in which the span identification is preceded by an ensemble sentence level classifier (SLC).We only perform span identification on those samples which are flagged as propaganda samples by the SLC Model.We perform token level classification by fine-tuning BERT and use CRF to perform sequence tagging.Additionally, we present our analysis of different voting ensembles for the SLC model.Our system ranks 14 th on the test set and 22 nd on the development set and with an F1 score of 0.41 and 0.39 respectively.