We prove a conditional expectation bang-bang principle. Based on properties of the conditional expectation vector measure, we establish that the conditional expectation of a set-valued mapping coincides with the conditional expectation of the set of selections of its extreme points part. As a by-product, we obtain straightforwardly a purification principle.

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Y. Askoura, M. Sbihi. “A Bang-Bang Principle for the Conditional Expectation Vector Measure.” Journal of Convex Analysis 33 (2026), No. 1&2, 377–392. https://doi.org/10.68381/jca33023