Network-based Neighborhood regression
Yaoming Zhen, Jin-Hong Du
TL;DR
This work introduces a network-based neighborhood regression (NBNR) framework that jointly leverages local neighborhood structure and global community information to model directional regulation between gene modules. By enforcing a block structure on the regression coefficients, the authors decompose the estimation into independent community-wise least squares problems (CLSE) with closed-form solutions and establish non-asymptotic, concentration-based guarantees, including unbiasedness and minimax optimality. The analysis shows a striking linear-in-$n$ consistency when the network is sufficiently dense and well-structured, illustrating the advantage of incorporating neighborhood information over classical root-$n$ convergence. The method is validated through simulations and applied to Autism Spectrum Disorder data, where it uncovers interpretable inter- and intra-community regulatory patterns and achieves superior predictive performance relative to network-naive approaches, while providing a novel adjusted $R^2$ measure for model fit in a networked, modular setting.
Abstract
Given the ubiquity of modularity in biological systems, module-level regulation analysis is vital for understanding biological systems across various levels and their dynamics. Current statistical analysis on biological modules predominantly focuses on either detecting the functional modules in biological networks or sub-group regression on the biological features without using the network data. This paper proposes a novel network-based neighborhood regression framework whose regression functions depend on both the global community-level information and local connectivity structures among entities. An efficient community-wise least square optimization approach is developed to uncover the strength of regulation among the network modules while enabling asymptotic inference. With random graph theory, we derive non-asymptotic estimation error bounds for the proposed estimator, achieving exact minimax optimality. Unlike the root-n consistency typical in canonical linear regression, our model exhibits linear consistency in the number of nodes n, highlighting the advantage of incorporating neighborhood information. The effectiveness of the proposed framework is further supported by extensive numerical experiments. Application to whole-exome sequencing and RNA-sequencing Autism datasets demonstrates the usage of the proposed method in identifying the association between the gene modules of genetic variations and the gene modules of genomic differential expressions.
