Structural learning of simple staged trees

Bayesian networks faithfully represent the symmetric conditional independences existing between the components of a random vector. Staged trees are an extension of Bayesian networks for categorical random vectors whose graph represents non-symmetric conditional independences via vertex coloring. How...

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Detalles Bibliográficos
Autores: Leonelli, Manuele, Varando, Gherardo
Tipo de recurso: artículo
Fecha de publicación:2024
País:España
Institución:IE
Repositorio:Repositorio IE
OAI Identifier:oai:repositorio.ie.edu:20.500.14417/3916
Acceso en línea:https://doi.org/10.1007/s10618-024-01007-0
https://hdl.handle.net/20.500.14417/3916
https://link.springer.com/article/10.1007/s10618-024-01007-0
Access Level:acceso abierto
Palabra clave:Asymmetric graphical models
Bayesian networks
Context-specific independence
Staged trees
Structural learning
33 Ciencias Tecnológicas
ODS 9 - Industria, innovación e infraestructura
Descripción
Sumario:Bayesian networks faithfully represent the symmetric conditional independences existing between the components of a random vector. Staged trees are an extension of Bayesian networks for categorical random vectors whose graph represents non-symmetric conditional independences via vertex coloring. However, since they are based on a tree representation of the sample space, the underlying graph becomes cluttered and difficult to visualize as the number of variables increases. Here, we introduce the first structural learning algorithms for the class of simple staged trees, entertaining a compact coalescence of the underlying tree from which non-symmetric independences can be easily read. We show that data-learned simple staged trees often outperform Bayesian networks in model fit and illustrate how the coalesced graph is used to identify non-symmetric conditional independences.