Reference-free Evaluation Metrics for Text Generation: A Survey
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Abstract (arXiv)
A number of automatic evaluation metrics have been proposed for natural language generation systems. The most common approach to automatic evaluation is the use of a reference-based metric that compares the model's output with gold-standard references written by humans. However, it is expensive to create such references, and for some tasks, such as response generation in dialogue, creating references is not a simple matter. Therefore, various reference-free metrics have been developed in recent years. In this survey, which intends to cover the full breadth of all NLG tasks, we investigate the most commonly used approaches, their application, and their other uses beyond evaluating models. The survey concludes by highlighting some promising directions for future research.
Key facts. Cited by 9 papers in the map (data through 14 Oct 2026). Builds on 74 of its 120 references that are in the map. First posted on arXiv 21 Jan 2025.
Builds on
74 of 120 references.
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Citing papers per year: 2025: 6; 2026: 3.
9 papers.
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