Constitutional AI: RLAIF and AI Alignment

Popularized by Anthropic, Constitutional AI is a method for training AI models to be helpful, harmless, and honest without relying solely on intensive human labeling.

The Two-Stage Process

1. Supervised Learning (Critique and Revision)

The model generates responses, critiques them based on a set of principles (the “constitution”), and then revises the response to be more aligned.

2. RLAIF (Reinforcement Learning from AI Feedback)

A “preference model” is trained using the AI’s own critiques. This preference model then guides the final fine-tuning of the main model through Reinforcement Learning.

Benefits

• Scalability: Reduces the need for thousands of human annotators.
• Transparency: The rules governing the model’s behavior are explicitly written out in the constitution.
• Consistency: AI feedback is often more consistent than varying human judgments over large datasets.