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Alignment training

As explained in Reinforcement Learning from Human Feedback

Value alignment is the conformity of an intelligent system's objectives and behavior to the values held by the people or population it is intended to serve.

Alignment training aims to make an intelligent system’s objectives and behavior conform to the values of the people or population it serves. In RLHF, human preferences become an optimizable learning signal rather than a fixed environment reward. section 5.0 section 10.1

Reward models operationalize this goal by compressing complex human judgments into scalar rewards or preference probabilities. The resulting proxy objective guides reinforcement learning, while empirical methods often optimize specific skills rather than directly measuring conformity to values. section 5.0 section 10.1

Alignment training connects several distinct problem settings:

  • RLHF learns reward signals from human preference comparisons instead of receiving fixed environment rewards. section 5.0
  • Inverse reinforcement learning estimates an agent’s reward function from behavioral trajectories, sharing the high-level alignment problem but differing in implementation and emphasis. section 5.0
  • Pluralistic alignment studies how systems can account for values across populations through research, datasets, and personalization. section 10.1

Preference-based reward

Given two candidate answers, a Bradley–Terry reward model predicts the probability that one answer is the preferred, higher-quality response; reinforcement learning can then optimize that learned signal. section 5.0

Figure 5.1 The RM in RLHF plays the role of the environment component that returns rewards in standard RL. The key difference is that in RLHF, we get to control and learn this reward function from human preferences, rather than it being fixed by the environment.
figure

Compare the learned reward model with the fixed environment component in standard reinforcement learning. section 5.0

How Reinforcement Learning from Human Feedback covers it

How deep it goes
Explains reward-model and preference-based mechanisms, but defers detailed data collection and reward-modeling procedures.
Examples
Uses pairwise preferred answers, Bradley–Terry reward models, and learned rewards replacing fixed environment rewards.
What it assumes
Assumes familiarity with reinforcement learning, optimization, human preferences, and modern deep learning systems.
What you can do after
Evaluate/understand how human preferences become proxy rewards and how empirical alignment differs from direct value calibration.
How it connects
Connects RLHF with reward modeling, reinforcement learning, inverse reinforcement learning, human preferences, and pluralistic alignment.

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Related concepts

This explainer was generated by Manning's knowledge graph from the text of Reinforcement Learning from Human Feedback. The section links point to the parts of the book it draws on.