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  3. /Perplexity
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Perplexity

A measurement of how well a language model predicts text.

Definition

A measurement of how well a language model predicts text. Lower perplexity means the model is less 'surprised' by the text it sees. Technically, it's the exponentiated average negative log-likelihood. Useful for comparing models but doesn't always correlate with usefulness for specific tasks.

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Related Terms

Evaluation

The process of measuring how well an AI model performs on its intended task.

Language Model

An AI model that understands and generates human language.

Benchmark

A standardized test used to measure and compare AI model performance.

Activation Function

A mathematical function applied to a neuron's output that introduces non-linearity into the network.

Adam Optimizer

An optimization algorithm that combines the best parts of two other methods — AdaGrad and RMSProp.

AGI

Artificial General Intelligence.

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