Preference data
Preference data is a collection of judgments or comparisons indicating the relative preference or quality of alternatives, often model outputs.
Reinforcement Learning from Human Feedback
A pairwise comparison is an evaluation that determines which of two items is preferred.
- How it is used
- Supplies proxy judgments for reward modeling, preference fine-tuning, and RLHF when desired behavior lacks a precise reward function.
- How deep it goes
- Details formats, on-policy sourcing, collection operations, and bias, while leaving pairwise adequacy and annotator demographics as open questions.
- Examples
- Uses Likert rankings, correct-versus-incorrect mathematical answers, constrained goldfish poems, and AI-judged completion pairs.
- What you can do after
- Operate/configure preference-data collection by selecting label formats, seeking on-policy generations, and monitoring transferable biases.
Read how Reinforcement Learning from Human Feedback explains preference data →
Machine Learning System Design
Pairwise comparison is an evaluation technique that asks a rater to compare two alternatives rather than assign an absolute score to one alternative.
- How it is used
- Frames pairwise comparison as a labeling design for evaluating alternatives such as chatbot responses.
- How deep it goes
- Explains ternary judgments and variance reduction, then qualifies majority voting without deriving a broader preference model.
- Examples
- Uses chatbot answers, correctness and tone criteria, ternary A-or-B judgments, and three labelers with 70% individual accuracy.
- What you can do after
- Evaluate alternatives with lower-variance ternary comparisons while checking whether labelers’ errors are correlated.
Read how Machine Learning System Design explains preference data →
Related concepts
- reward modelused by · A reward model is a learned model that assigns scores to outputs, actions, or outcomes to represent their desirability according to preferences or evaluation criteria.
- Direct Preference Optimizationused by · Direct Preference Optimization is a technique for training a model directly from preference data, such as preferred and dispreferred outputs, without separately fitting a reward model.
- reinforcement learning with human feedbackuses · Reinforcement learning with human feedback is a model-training approach that uses human evaluations or preferences to guide optimization of model behavior.
- preference tuninguses · Preference tuning is a model-training technique that adjusts a model’s behavior toward outputs favored by preference signals, judgments, objectives, or rewards.
- direct alignment algorithmused by · A direct alignment algorithm optimizes a model directly from preference data without learning an intermediate reward model or using a reinforcement-learning optimizer.
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