DAHL: Domain-specific Automated Hallucination Evaluation of Long-Form Text through a Benchmark Dataset in Biomedicine

We introduce DAHL, a benchmark dataset and automated evaluation system designed to assess hallucination in long-form text generation, specifically within the biomedical domain.

Our benchmark dataset, meticulously curated from biomedical research papers, consists of 8,573 questions across 29 categories.

DAHL evaluates fact-conflicting hallucinations in Large Language Models (LLMs) by deconstructing responses into atomic units, each representing a single piece of information.

The accuracy of these responses is averaged to produce the DAHL Score, offering a more in-depth evaluation of hallucinations compared to previous methods that rely on multiple-choice tasks.

We conduct experiments with 8 different models, finding that larger models tend to hallucinate less; however, beyond a model size of 7 to 8 billion parameters, further scaling does not significantly improve factual accuracy.

The DAHL Score holds potential as an efficient alternative to human-annotated preference labels, being able to be expanded to other specialized domains.

We release the dataset and code in public.

;Comment: EMNLP2024/FEVER