AI engineering glossary · Evaluation metrics
What is ROUGE-L?
ROUGE-L: A ROUGE variant based on the longest common subsequence between the generated and reference texts: the longest run of words appearing in both in the same order, though not necessarily adjacent. It captures sentence-level word order without fixing an n-gram length.
ROUGE-L: an example
Between 'the cat sat on the mat' and 'the cat on the mat', the longest common subsequence has 5 words, giving recall 5/6 and precision 5/5.
Related terms
More Evaluation metrics terms
- Slice-based evaluation
- Spearman's rank correlation
- Specificity
- Symmetric mean absolute percentage error
- Temperature scaling
- Token-level F1
- Translation edit rate
- True negative
Where you learn it
ROUGE-L is part of the AI Engineering Program, which teaches it with notes, a hands-on lab and an exam. The first lesson is free.