GECToR – Grammatical Error Correction: Tag, Not Rewrite
Table 7: Comparison of single models and ensembles. The M2 score for CoNLL-2014 (test) and ERRANT for the BEA-2019 (test) are reported. In ensembles we simply average output probabilities from single models.
['[BOLD] GEC system', '[BOLD] Ens.', '[BOLD] CoNLL-2014 (test)  [BOLD] P', '[BOLD] CoNLL-2014 (test)  [BOLD] R', '[BOLD] CoNLL-2014 (test)  [BOLD] F0.5', '[BOLD] BEA-2019 (test)  [BOLD] P', '[BOLD] BEA-2019 (test)  [BOLD] R', '[BOLD] BEA-2019 (test)  [BOLD] F0.5']
Finally, our best single-model, GECToR (XLNet) achieves F0.5 = 65.3 on CoNLL-2014 (test) and F0.5 = 72.4 on BEA-2019 (test). Best ensemble model, GECToR (BERT + RoBERTa + XLNet)