On the Interplay of Pre-Training, Mid-Training, and RL on Reasoning Language Models

arXiv — cs.CLTuesday, December 9, 2025 at 5:00:00 AM
  • Recent advancements in reinforcement learning (RL) techniques have significantly improved reasoning capabilities in language models. However, the extent to which post-training enhances reasoning beyond pre-training remains uncertain. A new experimental framework has been developed to isolate the effects of pre-training, mid-training, and RL-based post-training, utilizing synthetic reasoning tasks to evaluate model performance.
  • This development is crucial as it addresses the ambiguity surrounding the training processes of language models, which are often opaque and underexamined. By clarifying the contributions of different training phases, researchers can better understand how to enhance reasoning abilities in language models, potentially leading to more effective applications in various fields.
  • The exploration of reasoning in language models intersects with ongoing discussions about their limitations, such as the challenges in simulating diverse user responses and generating faithful self-explanations. These issues highlight the need for improved training methodologies and frameworks, as researchers seek to enhance the reliability and accuracy of language models in real-world applications.
— via World Pulse Now AI Editorial System

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