Neighborhood Elites: Quality-Diversity Search for Uncertainty Quantification in Question Answering
AspireAI community · arXiv
Neighborhood Elites recasts the input perturbation used to estimate a model's uncertainty in question answering as a quality-diversity search problem, so the rewrites deliberately cover two axes: the kind of edit, and how explicitly the context supports the answer. Across five extractive-QA datasets and five instruction-tuned LLMs, the authors report that it improves failure detection against every other neighborhood constructor in at least 24 of the 25 dataset-model pairs, reaching 0.726 AUROC and 0.211 AUPRC lift over the base rate. They also report it beats semantic entropy computed over decoder samples by 0.074 AUROC and 0.062 AUPRC lift, with the advantage widening as the neighborhood grows. The comparison holds the editor, QA model, uncertainty measure and search objective fixed, which isolates the neighborhood construction as the variable under test.
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