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Appendices A Further Common Assumptions for Causal Discovery

Neural Information Processing Systems

Following from Section 2.1, we review several relaxations of faithfulness, which give rise to different We provide further simulation results for the analysis of the SUCF assumption in Section 3.2 . Different number of nodes and expected degrees are considered. X-axes are visualized in log scale. With the above lemmas, we now provide the proofs of the main results. We proceed by contraposition in both parts of the proof.



Export Reviews, Discussions, Author Feedback and Meta-Reviews

Neural Information Processing Systems

First provide a summary of the paper, and then address the following criteria: Quality, clarity, originality and significance. Identifying conditional independence of variables in graphical models is a key to finding tractable solutions, and faithfulness is a key condition of these relationships. The authors provide necessary and sufficient conditions for determining faithfulness in Gaussian graphical models (based on partitioning variables outside the conditioning set into two disjoint subsets), and show how this theoretical result can be translated into an algorithm for determining if a distribution is faithful. PROS: - Clear, well-written paper with illustrative examples - Addresses a relevant problem and provides a meaningful theoretical result - Provides a practical test for faithfulness in Gaussian graphical model CONS: - Theoretical result is restricted to Gaussian graphical models Quality: This paper provides addresses a theoretical problem (faithfulness in Gaussian graphical models). The claims are well-reasoned and the proofs support the claims. The resulting algorithm provides a useful test of faithfulness.



Sparse Inverse Covariance Estimation with Calibration

Neural Information Processing Systems

We propose a semiparametric procedure for estimating high dimensional sparse inverse covariance matrix. Our method, named ALICE, is applicable to the elliptical family. Computationally, we develop an efficient dual inexact iterative projection (${\rm D_2}$P) algorithm based on the alternating direction method of multipliers (ADMM). Theoretically, we prove that the ALICE estimator achieves the parametric rate of convergence in both parameter estimation and model selection.



Linear Discriminant Analysis with Gradient Optimization on Covariance Inverse

arXiv.org Machine Learning

Linear discriminant analysis (LDA) is a fundamental method in statistical pattern recognition and classification, achieving Bayes optimality under Gaussian assumptions. However, it is well-known that classical LDA may struggle in high-dimensional settings due to instability in covariance estimation. In this work, we propose LDA with gradient optimization (LDA-GO), a new approach that directly optimizes the inverse covariance matrix via gradient descent. The algorithm parametrizes the inverse covariance matrix through Cholesky factorization, incorporates a low-rank extension to reduce computational complexity, and considers a multiple-initialization strategy, including identity initialization and warm-starting from the classical LDA estimates. The effectiveness of LDA-GO is demonstrated through extensive multivariate simulations and real-data experiments.


Reviews: Learning Identifiable Gaussian Bayesian Networks in Polynomial Time and Sample Complexity

Neural Information Processing Systems

In particular, it establishes that as long as noises are homoscedastic, then under a milder minimality/faithfulness assumptions it is possible to efficiently recover the GBN. Clarity The paper is heavy on notation, but everything is explained and organized clearly.