# Coloured Graphical Models and their Symmetries.

@article{Davies2020ColouredGM, title={Coloured Graphical Models and their Symmetries.}, author={Isobel Davies and Orlando Marigliano}, journal={arXiv: Algebraic Geometry}, year={2020} }

Coloured graphical models are Gaussian statistical models determined by an undirected coloured graph. These models can be described by linear spaces of symmetric matrices. We outline a relationship between the symmetries of the graph and the linear forms that vanish on the reciprocal variety of the model. In the special case of the uniform coloured n-cycle, this gives a complete description of all such linear forms.

## 2 Citations

MODEL SELECTION IN THE SPACE OF GAUSSIAN MODELS INVARIANT BY SYMMETRY

- Mathematics
- 2022

We consider multivariate centered Gaussian models for the random variable Z = (Z1, . . . ,Zp), invariant under the action of a subgroup of the group of permutations on {1, . . . , p}. Using the…

MODEL SELECTION IN THE SPACE OF GAUSSIAN MODELS INVARIANT BY SYMMETRY

- Mathematics
- 2020

We consider multivariate centred Gaussian models for the random variable Z = (Z1,. .. , Zp), invariant under the action of a subgroup of the group of permutations on {1,. .. , p}. Using the…

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