Learning Data Mining with Python

Chapter 8
The red lines indicate that the value is 0.5 when x is zero.
Each individual neuron receives its inputs and then computes the output based
on these values. Neural networks are simply networks of these neurons connected
together, and they can be very powerful for data mining applications. The
combinations of these neurons, how they fit together, and how they combine
to learn a model are one of the most powerful concepts in machine learning.
An introduction to neural networks
For data mining applications, the arrangement of neurons is usually in layers. The
first layer, the input layer, takes the inputs from the dataset. The outputs of each
of these neurons are computed and then passed along to the neurons in the next
layer. This is called a feed-forward neural network. We will refer to these simply
as neural networks for this chapter. There are other types of neural networks too
that are used for different applications. We will see another type of network in
Chapter 11, Classifying Objects in Images Using Deep Learning.
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