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arXiv · 1905.08196

Optimisation of Overparametrized Sum-Product Networks

Martin Trapp·Robert Peharz·Franz Pernkopf
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Abstract

It seems to be a pearl of conventional wisdom that parameter learning in deep sum-product networks is surprisingly fast compared to shallow mixture models. This paper examines the effects of overparameterization in sum-product networks on the speed of parameter optimisation. Using theoretical analysis and empirical experiments, we show that deep sum-product networks exhibit an implicit acceleration compared to their shallow counterpart. In fact, gradient-based optimisation in deep tree-structured sum-product networks is equal to gradient ascend with adaptive and time-varying learning rates and additional momentum terms.

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Martin Trapp, Robert Peharz, Franz Pernkopf. 2019-05-20. Optimisation of Overparametrized Sum-Product Networks. https://arxiv.org/abs/1905.08196

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