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Hidden layer

As explained in Inside AI

A hidden layer is an intermediate neural-network layer that transforms representations between the input and output layers.

A hidden layer sits between a neural network’s input and output layers. It helps turn input data into a prediction: the input layer receives the data, connections through the hidden layer carry learned information, and the output layer computes the result. section 3.3

The learning is stored in the weights on connections between nodes. Training starts with random weights, processes examples, compares predictions with correct labels, and adjusts the weights when predictions differ. In backpropagation, those adjustments move backward through the hidden layers. section 3.3

Following three inputs

Consider a network receiving 0.5, 0.6, and 0.2 as inputs. Each input node connects to nodes in the next layer through weighted connections. The example illustrates where a hidden layer sits; the three numbers alone do not specify what the network will predict. section 3.3

Figure 3.3 A backpropagation model with three layers
figure

The three-layer diagram shows the hidden layer’s position between input and output. section 3.3

A network can have more than one hidden layer. Adding hidden layers is a central distinction of deep learning: successive layers can build complex concepts from simpler ones, helping the network discern characteristics in data. The number of layers describes an architecture, not a prediction of its performance on a particular task. section 3.4

How Inside AI covers it

How deep it goes
Explains layer roles, weighted connections, and backward weight adjustment without providing implementation details.
Examples
Uses a three-layer diagram and numerical inputs of 0.5, 0.6, and 0.2.
What it assumes
Introduces the layer roles and node behavior using numerical inputs, without requiring code or formal mathematics.
What you can do after
Evaluate/understand where hidden layers sit and why deeper networks use multiple layers to build more complex concepts.
How it connects
Connects hidden layers to input and output layers, backpropagation, and deep learning.

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This explainer was generated by Manning's knowledge graph from the text of Inside AI. The section links point to the parts of the book it draws on.