arXiv Machine Learning By Sanna Jarl, Jens Sj\"olund, Jonathan J. S. Scragg, Maria B{\aa}nkestad

Correcting Boundary Bias and Observation Independence in Bayesian Experimental Design

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The paper tackles two shortcomings of Gaussian‑process based active learning: (1) the posterior variance is independent of observed values, reducing sensitivity to data structure, and (2) it over‑inflates variance near domain boundaries, causing excessive edge sampling. The authors propose a reconstruction‑driven design density that warps sampling toward regions where the posterior mean changes rapidly, and a geometric equalizer that corrects boundary bias. Experiments on sixteen synthetic and two real‑data benchmarks show that the equalizer consistently improves function reconstruction, while the warp further enhances performance by concentrating measurements where the target function varies most.

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