Semi-Parametric Model Editor with a Retrieval-Augmented Counterfactual Model
Memory-Based Model Editing at Scale
Model editors make local updates to the behavior of base (pre-trained) models to inject updated knowledge or correct undesirable behaviors.
Existing approaches to model editing have shown promise, but also suffer from insufficient expressiveness : they struggle to accurately model an edit s intended scope (examples affected by the edit), leading to inaccuratepredictions for test inputs loosely related to the edit, and they often fail altogether after many edits.
As a higher-capacity alternative, we propose semi-parametric editing with a retrieval-augmented counterfactual model(serac), which stores edits in an explicit memory and learns to reason over them to modulate the base model s predictions as needed.
We introduce three challenging language model editing problems based on question answering, fact-checking, and dialogue generation.
We find that only serac achieves high performance on all three problems, consistently outperforming existing approaches to model editing by a significant margin.
Authors
Eric Mitchell, Charles Lin, Antoine Bosselut, Christopher D. Manning, Chelsea Finn