Confident but Wrong: A Constrained Decoding Diagnostic for Low-Resource Automatic Post-Editing
Isuru Wijesiri and others
In Findings of the Association for Computational Linguistics: EMNLP 2026, 2026
A black-box, inference-time diagnostic for automatic post-editing (APE) that varies an edit-distance penalty between free editing and copying the machine-translation output. The resulting TER-vs-penalty curve exposes two systematic failure modes of low-resource fine-tuning, Binary Collapse and Confident Miscalibration, and prescribes a fix. The work releases the first English-Sinhala ( 66k) and a new English-Tamil ( 39k) APE datasets.