activity
20122026
most citedThe Lukacs-Olkin-Rubin theorem on symmetric cones without invariance of the "quotient"

15 citations · 67 across the 29 of their papers we have counts for

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10 papers · 1 filter

math.ST2026

A new class of colored Gaussian graphical models with explicit normalizing constants

Adam Chojecki, Piotr Graczyk, Hideyuki Ishi +1

We study Bayesian model selection in colored Gaussian graphical models (CGGMs), which combine sparsity of conditional independencies with symmetry constraints encoded by vertex- an…

math.ST2025

Identifying Network Hubs with the Partial Correlation Graphical LASSO

Małgorzata Bogdan, Adam Chojecki, Ivan Hejný +2

Graphical LASSO (GLASSO) is a widely used method for estimating sparse precision matrices and learning undirected graphical models in high-dimensional settings. Because GLASSO pena…

math.ST2025

From Graphical Lasso to Atomic Norms: High-Dimensional Pattern Recovery

Piotr Graczyk, Bartosz Kołodziejek, Hideto Nakashima +1

We study high-dimensional precision-matrix estimation with polyhedral atomic-norm penalties on the off-diagonal entries. This framework covers the graphical lasso, -ty…

math.ST2022

Analysis of Conditional Randomisation and Permutation schemes with application to conditional independence testing

Małgorzata Łazęcka, Bartosz Kołodziejek, Jan Mielniczuk

We study properties of two resampling scenarios: Conditional Randomisation and Conditional Permutation schemes, which are relevant for testing conditional independence of discrete…

math.ST2022

Graphical Gaussian models associated to a homogeneous graph with permutation symmetries

Piotr Graczyk, Hideyuki Ishi, Bartosz Kołodziejek

We consider multivariate centered Gaussian models for the random vector , whose conditional structure is described by a homogeneous graph and which is invariant…

math.ST2022

Pattern recovery by SLOPE

Małgorzata Bogdan, Xavier Dupuis, Piotr Graczyk +4

SLOPE is a popular method for dimensionality reduction in the high-dimensional regression. Indeed some regression coefficient estimates of SLOPE can be null (sparsity) or can be eq…

math.ST2022

Pattern recovery and signal denoising by SLOPE when the design matrix is orthogonal

Tomasz Skalski, Piotr Graczyk, Bartosz Kołodziejek +1

Sorted Penalized Estimator (SLOPE) is a relatively new convex regularization method for fitting high-dimensional regression models. SLOPE allows to reduce the model dimens…

math.ST2020

Model selection in the space of Gaussian models invariant by symmetry

Piotr Graczyk, Hideyuki Ishi, Bartosz Kołodziejek +1

We consider multivariate centered Gaussian models for the random variable , invariant under the action of a subgroup of the group of permutations on $\{1,\ldot…

math.ST2018

Location and scale behaviour of the quantiles of a natural exponential family

Mauro Piccioni, Bartosz Kołodziejek, Gérard Letac

Let be a probability on the real line generating a natural exponential family . Fix in We show that the property that $P_t((-\infty,t)…

math.ST2018★ 4 cited

Wishart laws and variance function on homogeneous cones

Piotr Graczyk, Hideyuki Ishi, Bartosz Kołodziejek

We present a systematic study of Riesz measures and their natural exponential families of Wishart laws on a homogeneous cone. We compute explicitly the inverse of the mean map and…