Asymptotically Minimax Robust Hypothesis Testing

The design of asymptotically minimax robust hypothesis testing is formalized for the Bayesian and Neyman-Pearson tests of Type I and II. The uncertainty classes based on the KL-divergence, αdivergence, symmetrized α-divergence, total variation distance, as well as the band model, moment classes and p-point classes are considered. It is shown with a counterexample that minimax robust tests do not always exist. Implications between single sample-, all-sampleand asymptotic minimax robustness are derived. Existence and uniqueness of asymptotically minimax robust tests are proven using Sion’s minimax theorem and the Karush-Kuhn-Tucker multipliers. The least favorable distributions and the corresponding robust likelihood ratio functions are derived in parametric forms, which can then be determined by solving a system of equations. The proposed theory proves that Dabak’s design does not produce any asymptotically minimax robust test. A generalization of the theory to multiple-, decentralizedand sequential hypothesis testing is discussed. The derivations are evaluated, examplified and applied to spectrum sensing.