TAXI: Evaluating Categorical Knowledge Editing for Language Models
Derek Powell, Walter Gerych, Thomas Hartvigsen
TL;DR
TAXI introduces a taxonomy-based benchmark to evaluate consistency in categorical knowledge editing for LLMs, addressing the problem that edits should propagate to inherited properties to maintain a coherent world model. It defines categories $c \\in \\mathcal{C}$ with property sets $p^c$, subjects $s$, and a formal editing process that tests whether changing a subject’s category leads to correct changes in its properties through metrics including Edit Success, Invariance, and Consistency. Experiments on Llama-2 editors reveal high forward edit success but substantially lower property-consistency, with invariance outperforming consistency and atypical subjects editing more easily, indicating room for improved generalization. A human study shows near-perfect property generalization, underscoring the gap between current editors and human cognition and highlighting TAXI as a principled, human-solvable benchmark for advancing consistent model editing and safer factual updates.
Abstract
Humans rarely learn one fact in isolation. Instead, learning a new fact induces knowledge of other facts about the world. For example, in learning a korat is a type of cat, you also infer it is a mammal and has claws, ensuring your model of the world is consistent. Knowledge editing aims to inject new facts into language models to improve their factuality, but current benchmarks fail to evaluate consistency, which is critical to ensure efficient, accurate, and generalizable edits. We manually create TAXI, a new benchmark dataset specifically created to evaluate consistency in categorical knowledge edits. TAXI contains 11,120 multiple-choice queries for 976 edits spanning 41 categories (e.g., Dogs), 164 subjects (e.g., Labrador), and 183 properties (e.g., is a mammal). We then use TAXI to evaluate popular editors' categorical consistency, measuring how often editing a subject's category appropriately edits its properties. We find that 1) the editors achieve marginal, yet non-random consistency, 2) their consistency far underperforms human baselines, and 3) consistency is more achievable when editing atypical subjects Our code and data are available at https://github.com/derekpowell/taxi.
