Offline Learning
Offline learning, also known as batch learning, is a paradigm in machine learning where the model is trained on a comprehensive, fixed dataset in a single or limited number of intensive training sessions. Once this training phase is completed, the model's parameters are not updated further, and it operates with the knowledge it has acquired during this phase
This approach contrasts with online learning, where models continuously update their parameters in response to new data streams. Offline learning is suitable for situations where the complete dataset is available beforehand and the environment is relatively stable, such that the patterns the model learns are not expected to change significantly over time.
It is often used when computational resources for training are only intermittently available or when the model needs to be robust and stable without the risk of drift due to new data.
A classic example of offline learning is the training of a spam filter using a pre-collected dataset of emails manually labeled as "spam" or "not spam." The model, possibly a decision tree or neural network, learns to classify emails based on this dataset. After training, the model is deployed to filter emails but does not adapt to new types of spam over time unless it is explicitly retrained with an updated dataset.
Another example is in the training of deep learning models for image recognition tasks, where a neural network is trained on a large, labeled dataset like ImageNet. Once training is complete, the model can classify images it has never seen before based on the learned patterns but does not update its knowledge unless retrained with new data.