Neural Networks

Internal

• Machine Learning

Individual Neuron

This is a representation of a logistic unit with a sigmoid (logistic) activation function.

The θ vector represents the model's parameters (model's weights). For a multi-layer neural network, the model parameters are collected in matrices named Θ, which will be describe below.

The bias unit is optional, but when it is provided, it is always 1.

Multi-Layer Neural Network

When the output