Sum Product Networks
Useful Papers:

SumProduct Networks: A New Deep Architecture
PDF
Original Paper, 2011

The SumProduct Theorem: A Foundation for Learning Tractable Models
PDF
SPN theorem, 2016

On the Latent Variable Interpretation in SumProduct Networks
PDF
Understanding latent variables

On Theoretical Properties of SumProduct Networks
PDF
Some theoretical results in SPN

Approximation Complexity of Maximum A Posteriori Inference in SumProduct Networks
PDF
MAP in SPN, complexity results.

On the Relationship between SumProduct Networks and Bayesian Networks
PDF
SPN to BN, 2015.

Learning Selective SumProduct Networks
PDF
Learning Selective SPNs, 2014.
Other Resources on/related to SPN:

SumProduct Networks lecture
Youtube
by Pascal Poupart

MAP in SPN: Original paper proposal
Youtube
by Pedro

Foundations of SumProduct Networks for Probabilistic Modeling
PDF
Ph.D thesis of Robert Peharz

A Differential Approach to Inference in Bayesian Networks
PDF
Darwiche's paper, Differential of network polynomial

Exhaustive list of SPN resources,
here
Refresher/Helper links:

GMM Refresher
PDF
by Zhiyao Duan & Bryan Pardo, Machine Learning: EECS 349 Fall 2012
AND/OR Search
Useful Papers

AND/OR Search Spaces for Graphical Models
PDF
Good initial discussion of the concept. R. Dechter and R. Mateesc. 2007

AND/OR Search Strategies for Combinatorial Optimization in Graphical Models
PDF
Radu Thesis. Radu Marinescu. 2008

AND/OR Search Spaces for Graphical Models
PDF
MMAP using AND/OR search, 2014
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