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HOW MODELS WORK

Weights.

Model weights · open weights

Learned numerical values that control how signals are combined inside a model.

In plain words

Weights are parameters used to scale and combine values in a model’s calculations. Training adjusts them so the model’s outputs better match its objective.

A closer look

In a simple model, y = wx + b, the weight w determines how strongly input x affects the prediction, while b is a bias. Neural networks use large arrays of weights across many operations. Individual weights usually cannot be read as isolated facts or instructions; behavior emerges from their interactions with the architecture and input.

After training, weights are saved in a checkpoint and loaded to run inference. “Model weights” is also used loosely for the full collection of saved parameters. An open-weight release makes those values available under a license, but does not necessarily include the training data or all the code needed to reproduce training.

In practice

AN EXAMPLE

A simple price model may learn that floor area should have a positive influence on its estimate. In a language model, weights participate in far more complex transformations of token representations.

A useful distinction

Weights are not the same as the temporary attention scores computed for a particular input. And access to weights is not automatically unrestricted permission to use them: the release’s license still determines the terms.

Watch & learn

Sources & further reading

Google — Machine learning reference: weight (opens in a new tab)