Covariate-Elaborated Robust Partial Information Transfer with Conditional Spike-and-Slab Prior
Ruqian Zhang, Yijiao Zhang, Annie Qu, Zhongyi Zhu, Juan Shen
TL;DR
This work tackles data heterogeneity and the inefficiency of global similarity transfer in high-dimensional settings. It introduces CONCERT, a Bayesian method that uses a conditional spike-and-slab prior to enable covariate-specific partial information transfer across multiple sources, while a standard spike-and-slab handles target variable selection. A scalable variational Bayes implementation provides practical inference, with theoretical guarantees for true-posterior and VB posterior contraction, and variable/similarity selection consistency. Empirical results from simulations and real data (GTEx and Lending Club) demonstrate robust performance, showing meaningful gains when sources share partial information and mitigating negative transfer in heterogeneous settings.
Abstract
The popularity of transfer learning stems from the fact that it can borrow information from useful auxiliary datasets. Existing statistical transfer learning methods usually adopt a global similarity measure between the source data and the target data, which may lead to inefficiency when only partial information is shared. In this paper, we propose a novel Bayesian transfer learning method named ``CONCERT'' to allow robust partial information transfer for high-dimensional data analysis. A conditional spike-and-slab prior is introduced in the joint distribution of target and source parameters for information transfer. By incorporating covariate-specific priors, we can characterize partial similarities and integrate source information collaboratively to improve the performance on the target. In contrast to existing work, the CONCERT is a one-step procedure which achieves variable selection and information transfer simultaneously. We establish variable selection consistency, as well as estimation and prediction error bounds for CONCERT. Our theory demonstrates the covariate-specific benefit of transfer learning. To ensure the scalability of the algorithm, we adopt the variational Bayes framework to facilitate implementation. Extensive experiments and two real data applications showcase the validity and advantages of CONCERT over existing cutting-edge transfer learning methods.
