• Corpus ID: 235303703

Locally associated graphical models and mixed convex exponential families

  title={Locally associated graphical models and mixed convex exponential families},
  author={Steffen L. Lauritzen and Piotr Zwiernik},
The notion of multivariate total positivity has proved to be useful in finance and psychology but may be too restrictive in other applications. In this paper we propose a concept of local association, where highly connected components in a graphical model are positively associated and study its properties. Our main motivation comes from gene expression data, where graphical models have become a popular exploratory tool. The models are instances of what we term mixed convex exponential families… 

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