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A simple learning module: A Restricted Boltzmann Machine

• We restrict the connectivity to make learning easier. – Only one layer of hidden units. • We will worry about multiple layers later – No connections between hidden units. • In an RBM, the hidden units are independent given the visible states.. – So we can quickly get an unbiased sample from the posterior distribution over hidden “causes” when given a data-vector :

hidden

j

i

visible