The complement of a value refers to what is left over when that value is subtracted from the whole. In statistics, the complement of a probability or significance level represents the probability of an event not happening.
Related terms
Union: The union of two events includes all outcomes that belong to either one or both events.
Intersection: The intersection of two events includes only outcomes that belong to both events.
Complementary Events: Two events are considered complementary if they cover all possible outcomes and cannot occur simultaneously.