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Home/Glossary/Perplexity
AI Glossary Term

What does “Perplexity” mean?

Definition

A language-model metric measuring how surprised the model is by true next tokens.

Related terms

Pass@k
A code-evaluation metric measuring the chance that at least one of k generated samples passes the tests.
Context Window
The maximum amount of input tokens a language model can process at once.
Top-k Sampling
A decoding strategy that samples only from the k most likely next tokens.
Confidence Interval
A statistical range that likely contains the true value of a measured model metric.
Frequency Penalty
A decoding setting that reduces the probability of tokens proportionally to how often they've appeared so far.
Presence Penalty
A decoding setting that reduces the probability of tokens that have appeared at all, encouraging new topics.

Learn more in our free guides

Mirostat Perplexity ControlPerplexity and Language MetricsPerplexity AI

See also

Parameter-Efficient Fine-Tuning (PEFT)PipelineParameterPrecisionOverfittingPretrainingOpen-Source ModelPrompt
PreviousParameter-Efficient Fine-Tuning (PEFT)NextPipeline
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