A Covariate Changes the Choice, Not Merely the Predicted Response
Abstract
Contextual Gaussian-process selection and covariate-indexed design selection should be evaluated through the actions they recommend. Conditional response variation does not necessarily imply a different preferred design. Evaluation retains variables available before action and examines local choice reversals, with sparse-context loss reported beside the population average. This focused synthesis develops an empirical comparison that preserves the terminal action, observation process, and total verification cost. Its proposed tests are prospective; no new simulation run, model-training result, or intervention effect is reported.
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