Freeze
Freezing is the practice of keeping selected model parameters unchanged during training or adaptation, typically while allowing other parameters to be updated.
Deep Learning with R, Third Edition
A frozen parameter is a model parameter excluded from optimization so that its value remains unchanged during further training.
- How it is used
- Preserves pretrained image features while training a classifier and reduces trainable parameters during large language model fine-tuning.
- How deep it goes
- Defines freezing, demonstrates trainable-weight changes and recompilation, then explains its memory role in LoRA without detailing optimizer internals.
- Examples
- Shows an Xception backbone with zero trainable weights and a frozen projection kernel paired with rank-eight LoRA matrices.
- What you can do after
- Apply it via Keras or KerasHub to freeze pretrained weights, check trainability, and recompile before training.
Read how Deep Learning with R, Third Edition explains freeze →
Deep Learning with Python, Third Edition
To keep selected model parameters unchanged during training so they do not receive optimizer updates.
- How it is used
- Protects pretrained representations while a new classifier learns, then supports controlled adaptation during fine-tuning.
- How deep it goes
- Defines weight immutability, shows Keras configuration and recompilation, and gives staged and partial fine-tuning procedures.
- Examples
- Uses a frozen Xception convolutional base, dense classifier, augmented image dataset, trainable-weight counts, and staged fine-tuning.
- What you can do after
- Operate/configure Keras models by freezing bases, training replacement classifiers, recompiling, and selectively unfreezing layers.
Read how Deep Learning with Python, Third Edition explains freeze →
Related concepts
- transfer learningcontrasts with · Transfer learning is a machine-learning technique that reuses knowledge learned from one task, domain, or dataset to improve learning or performance on another.
- warm startcontrasts with · Warm start is a technique that initializes training or optimization from prior parameters, data, or a related solution instead of starting from scratch.
- expert networkconfigures · An expert network is a specialized neural subnetwork within a mixture-of-experts model that processes inputs selected or routed to it by a gating mechanism.
- foundational modelconfigures · A base or foundation model is a pretrained model that provides learned parameters or capabilities as a starting point for reuse or adaptation to downstream tasks.
- fine-tuninguses · Fine-tuning is adapting a pretrained machine-learning model by training it further on targeted data or objectives for a task, domain, or behavior.
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