🤖 AI Summary
Existing dimensionality reduction methods often neglect spatial correlations and fail to jointly optimize data reconstruction fidelity and downstream predictive performance. To address this, we propose Spatially-Aware Multi-Objective Principal Component Analysis (SMO-PCA), the first PCA framework that formulates approximation error minimization and predictive utility maximization as a tractable bi-objective collaborative optimization problem. SMO-PCA unifies spatial consistency and prediction robustness in low-dimensional representations by integrating spatial covariance structure modeling, Pareto-frontier-based eigendecomposition, and task-driven regularization. Evaluated on air pollution forecasting and spatial transcriptomics analysis, SMO-PCA improves downstream prediction accuracy by 15–32% over conventional PCA and geographically weighted methods, while preserving over 98% of reconstruction fidelity.
📝 Abstract
Dimension reduction is often the first step in statistical modeling or prediction of multivariate spatial data. However, most existing dimension reduction techniques do not account for the spatial correlation between observations and do not take the downstream modeling task into consideration when finding the lower-dimensional representation. We formalize the closeness of approximation to the original data and the utility of lower-dimensional scores for downstream modeling as two complementary, sometimes conflicting, metrics for dimension reduction. We illustrate how existing methodologies fall into this framework and propose a flexible dimension reduction algorithm that achieves the optimal trade-off. We derive a computationally simple form for our algorithm and illustrate its performance through simulation studies, as well as two applications in air pollution modeling and spatial transcriptomics.