Revisiting Generalization Across Difficulty Levels: It's Not So Easy
Quick summary
arXiv:2511.21692v3 Announce Type: replace-cross Abstract: We investigate how well large language models (LLMs) generalize across different task difficulties, a key question for effective data curation and evaluation. Existing research is mixed regarding whether training on easier or harder data leads to better results, and whether those gains come on easier or harder test data. We address this question by conducting a systematic evaluation of LLMs' generalization across models, datasets, and fine-grained groups of example difficulty. We rank examples in six datasets using the outputs of thousa
Key takeaways
- arXiv:2511.21692v3 Announce Type: replace-cross Abstract: We investigate how well large language models (LLMs) generalize across different task difficulties, a key question for effective data curation and evaluation.
- Existing research is mixed regarding whether training on easier or harder data leads to better results, and whether those gains come on easier or harder test data.
- We address this question by conducting a systematic evaluation of LLMs' generalization across models, datasets, and fine-grained groups of example difficulty.
Why it matters
“Revisiting Generalization Across Difficulty Levels: It's Not So Easy” highlights the need for repeatable measurement rather than a single impressive demonstration. Independent validation across datasets and clearly stated limitations determine whether a result can guide product decisions.

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