Language Model RL

Creator
Creator
Seonglae ChoSeonglae Cho
Created
Created
2023 Sep 9 17:8
Editor
Edited
Edited
2026 Sep 17 16:3
Language Model RL Methods
 
 
 
Language Model Reward Benchmarks
 
 
 
Reinforcement Learning Transformers
 
 
Language Model RL Frameworks
 
 
 
 
 

SFT builds the parts. RL learns to combine them

Era of Experience

However, it has low
Sample efficiency
in larger samples and only finds better reasoning paths within its existing capacity which makes its total problem solving coverage smaller

Agent RL vulnerability

Search LLMs trained with agentic RL may appear safe, but can be easily jailbroken by manipulating the timing of the search step. The RL objective itself fails to suppress harmful queries, making "search first" behavior a critical vulnerability.
Information density (bits/sample) is very low in early training.
Sample efficiency
Supervised learning provides the correct answer for every token, always obtaining a lot of information, but RL only has high information when the probability of a correct answer is around 50%. In the early stages of RL, there are almost no correct samples, leading to extreme gradient variance.
async RL: cut off sampling on easy problems early and dynamically redirect that compute to hard prompts
 
 

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