 Let formula_2 denote a random vector (corresponding to the measurements), taken from a parametrized family of probability density functions or probability mass functions formula_3, which depends on the unknown deterministic parameter formula_4.The parameter space formula_5 is partitioned into two disjoint sets formula_6 and formula_7.Let formula_8 denote the hypothesis that formula_9, and let formula_10 denote the hypothesis that formula_11.