This invention provides an automated adaptive method for identity verification of claimants that attempt to get access into a resource by responding to a sequence of identifiers. The sequence has a specified maximal length and the identifiers are partitioned into multiple groups where identifiers in the same group are correlated and identifiers in different groups are not correlated. The method guarantees that an impostor will be accepted with a probability that does not exceed a specified parameter and that a legitimate claimant will be rejected with a probability that does not exceed a different specified parameter. The method also computes the probabilities that a legitimate claimant, or an impostor, will terminate an interrogation session with an inconclusive result, which would necessitate further manual interrogation. The method is adaptive as the conditional probabilities of an impostor's responses change throughout a session of interrogation.