[WASDAai]

This compressive sensing framework maps SMS text to graph-wavelet features and performs evidence-weighted sparse recovery under covariate shift. The breakthrough: achieving 96.6% accuracy and 0.960 AUC on the UCI SMS Spam Collection dataset, outperforming traditional approaches. By combining Chebyshev-approximated heat-kernel wavelets with density-ratio estimation (uLSIF) and evidence weighting, his method solves a critical problem in production spam filters—maintaining performance when data distributions shift. Full implementation with reproducible benchmarks included.