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Language AI

Direct Preference Optimization

Direct Preference Optimization (DPO) is a way to align language models with human preferences without training a separate reward model or running…

2 min readRead
Language AI

Reward Modeling

A reward model is a neural network trained to predict how good an AI response is, acting as an automated stand-in for human judgment.

2 min readRead
Language AI

Proximal Policy Optimization

Proximal Policy Optimization (PPO) is the reinforcement learning algorithm most associated with fine-tuning language models from human feedback.

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Language AI

Beam Search

Beam search is a decoding strategy that keeps the several most promising partial sequences at each step instead of greedily committing to one.

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Language AI

Nucleus and Top-k Sampling

Nucleus (top-p) and top-k sampling are decoding methods that add controlled randomness to text generation by restricting which tokens can be chosen.

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Language AI

Masked Language Modeling

Masked language modeling teaches an AI to fill in deliberately hidden words using the full surrounding context, both left and right.

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Language AI

Next-Token Prediction

Next-token prediction is the deceptively simple objective behind GPT-style models: given everything so far, guess the next chunk of text.

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Language AI

Sequence-to-Sequence Models

Sequence-to-sequence models map one sequence to another of possibly different length, like translating a sentence or summarizing a document.

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Language AI

Encoder-Decoder Architectures

Encoder-decoder architectures split a model into two halves: one that reads and compresses an input into a rich internal representation, and one…

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Language AI

Cross-Attention

Cross-attention is the mechanism that lets one sequence look at another: a decoder generating text can attend to an encoder's representation of the input.

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Language AI

Catastrophic Forgetting

Catastrophic forgetting is when a neural network learns a new task and abruptly loses its ability to perform tasks it had already mastered.

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