Sampling Parameters

Sampling parameters control how language models choose the next token during generation. They directly affect the randomness, coherence, and creativity of outputs, making them critical tools for fine-tuning model behavior.

Core Parameters

  • Temperature: Controls randomness by adjusting the shape of the probability distribution. Lower values = more deterministic, higher = more diverse. See: Temperature (Sampling Parameter)

  • Top-K Sampling: Limits token selection to the top K most probable tokens. Reduces risk of low-probability junk while allowing variation. See: Top-K Sampling

  • Top-P Sampling (Nucleus): Chooses from the smallest set of tokens whose cumulative probability exceeds P. More dynamic than Top-K. See: Top-P (Nucleus Sampling)

  • Frequency Penalty: Decreases the likelihood of a token being selected again based on its frequency in the current text. Helps reduce repetition.

  • Presence Penalty: Penalizes tokens that have already appeared, regardless of frequency. Encourages topic diversity.

  • Max Tokens: Limits the total number of tokens generated in a response.

  • Stop Sequences: Specifies one or more sequences that signal the model to stop generating further output.

Tuning Strategy

  • Use low temperature + top-k for accuracy and structure.
  • Use higher temperature + top-p for creativity or ideation tasks.
  • Combine with penalties to manage repetition and focus.
  • A balanced starting point is temperature 0.2, top-P 0.95, top-K 30 for coherent but creative results.
  • Use Temperature 0 for factual tasks.

Practical Use Cases

  • Chatbots: Tune for consistency and tone.
  • Content Generation: Balance creativity and relevance.
  • Code Completion: Favor deterministic generation for reliability.