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language-models

Next-token prediction and perplexity

taught

A language model as a distribution over the next token given the ones before it; the chain rule factors a sequence's probability into a product of these conditionals, and perplexity turns average per-token surprise into one comparable number.

Taught in

Requires

  • n-gram-language-models recommended

    deep-learning ch.18 teaches the n-gram language model and perplexity as an RNN-motivating example; this course reuses the same definition and extends it to the LLM setting.

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Local knowledge map

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Solid arrows are required prerequisites; dashed are recommended or helpful. Lower rows are more foundational. Click any box to jump to that concept.