proposition: Lemma expectation_ge0 (X : {RV P >-> R}) : (forall x, 0 <= X x)%R -> 0 <= 'E_P[X].
proof: Proof. by move=> ?; rewrite unlock integral_ge0// => x _; rewrite lee_fin. Qed.
imports: mathcomp(all_ssreflect) mathcomp(ssralg poly ssrnum ssrint interval finmap) mathcomp(mathcomp_extra boolp classical_sets functions) mathcomp(cardinality) HB(structures) exp numfun lebesgue_measure lebesgue_integral reals ereal signed topology normedtype sequences esum measure exp numfun lebesgue_measure lebesgue_integral