Imagine training a team where the same few people always do the work. The others never learn. Dropout prevents this by randomly removing neural-network units during training, giving different units opportunities to update their weights and reducing overfitting. section 10.2
During training, dropout works as a simple repeating procedure:
- Train the remaining network and update its weights through backpropagation. section 10.2 section 10.6
Dropout in a Keras classifier
A classifier for a two-feature circular dataset uses hidden layers of 128 and 64 ReLU units, with Dropout(.2) between them. The value .2 specifies the dropout probability used in those layers. The model ends with a two-unit softmax output and is trained with categorical cross-entropy and Adam. section 10.3











