In Restricted Boltzmann Machine (RBM), we define the energy function $E(\mathbf{v}, \mathbf{h}; \, \mathbf{W}, \mathbf{a}, \mathbf{b})$.
- $\mathbf{v}$ is visible unit
- $\mathbf{h}$ is hidden unit
- $\mathbf{W}$ is the connection matrix between $\mathbf{v}$ and $\mathbf{h}$
- $\mathbf{a}, \mathbf{b}$ are the bias vector for visible and hidden units
And the aim is to learn the parameter $\mathbf{W}$, $\mathbf{a}$ and $\mathbf{b}$. from the training sample.
My question: What is the intuition behind this setup? In particular, the concept of energy function $E$ is not found in other machine learning methods (e.g. ANN, CNN ...etc).
I know that RBM is related to statistical mechanics in Physics (e.g. Ising Model and Inverse Ising Problem), but I don't really understand why such concept is useful in machine learning.
Related paper: Restricted Boltzmann Machines for Collaborative Filtering
Thanks.