How an RBM defines the probabilities of
hidden and visible vectors
The weights in an RBM define p(h|v) and p(v|h) in a very
straightforward way (lets ignore biases for now)
To sample from p(v|h), sample the binary state of
each visible unit from a logistic that depends on its
weight vector times h.
To sample from p(h|v), sample the binary state of
each hidden unit from a logistic that depends on its
weight vector times v.
If we use these two conditional distributions to do
alternating Gibbs sampling for a long time, we can get
p(v) or p(h)
i.e. we can sample from the model’s distribution over
the visible or hidden units.