Restricted Boltzmann Machines (Smolensky ,1986, called them “harmoniums”)

• We restrict the connectivity to make learning easier. – Only one layer of hidden units. • We will deal with more layers later – No connections between hidden units. • In an RBM, the hidden units are conditionally independent given the visible states. – So we can quickly get an unbiased sample from the posterior distribution when given a data-vector. – This is a big advantage over directed belief nets

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