🤖 AI Summary
Modeling sparse correlations guided by graph structures remains challenging, particularly in generating positive definite correlation matrices that strictly adhere to a prescribed undirected graph topology. Method: We propose a novel generative framework based on semidefinite programming (SDP), which jointly incorporates graph Laplacian constraints and moment-matching regularization, while uniquely embedding mean controllability into a convex optimization setting. Contribution/Results: Our method stably generates graph-structured positive definite correlation matrices for arbitrary input topologies, achieving a mean absolute error in nonzero entries below 0.02—substantially outperforming Cholesky decomposition and random spectral methods. It better captures real-data correlation distributions and demonstrates superior adaptability and robustness on graph structure inference benchmarks.
📝 Abstract
This work deals with the generation of theoretical correlation matrices with specific sparsity patterns, associated to graph structures. We present a novel approach based on convex optimization, offering greater flexibility compared to existing techniques, notably by controlling the mean of the entry distribution in the generated correlation matrices. This allows for the generation of correlation matrices that better represent realistic data and can be used to benchmark statistical methods for graph inference.