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Bias tensor

A rank-2 tensor with all neuron biases in a neural network:

\[\begin{equation*}
  \vec{b}^{[i]}
  =
  \begin{pmatrix}
    b^{[i]}_1 \\ \vdots \\ b^{[i]}_p
  \end{pmatrix}
  \in \mathbb{R}^p
\end{equation*}
\]

where

• \(b^{[i]}\) are all biases of the \(i\)-th layer
• \(b^{[i]}_j\) is the bias of the \(j\)-th neuron in the \(i\)-th layer

and

• \(i\) is the layer number
• \(p\) is the number of neurons in the \(i\)-th layer.