Duttweiler Luke, Almudevar Anthony
Linear Algebra Appl. 2024 Dec 15;703:78-108. doi: 10.1016/j.laa.2024.09.002. Epub 2024 Sep 10.
Recent developments in the spectral theory of Bayesian Networks has led to a need for a developed theory of estimation and inference on the eigenvalues of the normalized precision matrix, . In this paper, working under conditions where and remains fixed, we provide multivariate normal asymptotic distributions of the sample eigenvalues of under general conditions and under normal populations, a formula for second-order bias correction of these sample eigenvalues, and a Stein-type shrinkage estimator of the eigenvalues. Numerical simulations are performed which demonstrate under what generative conditions each estimation technique is most effective. When the largest eigenvalue of is small the simulations show that the second order bias-corrected eigenvalue was considerably less biased than the sample eigenvalue, whereas the smallest eigenvalue was estimated with less bias using either the sample eigenvalue or the proposed shrinkage method.
贝叶斯网络谱理论的最新进展引发了对归一化精度矩阵特征值估计和推断的完善理论的需求。在本文中,在( )和( )保持固定的条件下,我们给出了一般条件下以及正态总体下( )样本特征值的多元正态渐近分布、这些样本特征值的二阶偏差校正公式以及特征值的斯坦因型收缩估计量。进行了数值模拟,展示了每种估计技术在何种生成条件下最为有效。当( )的最大特征值较小时,模拟表明二阶偏差校正后的特征值比样本特征值的偏差要小得多,而使用样本特征值或所提出的收缩方法估计最小特征值时偏差较小。