Cross-cultural studies indicate that the "g" factor can be observed whenever a battery of diverse, complex cognitive tests is administered to a human sample. The factor structure of IQ tests has also been found to be consistent across sexes and ethnic groups in the U.S. and elsewhere. The "g" factor has been found to be the most invariant of all factors in cross-cultural comparisons. For example, when the "g" factors computed from an American standardization sample of Wechsler's IQ battery and from large samples who completed the Japanese translation of the same battery were compared, the congruence coefficient was .99, indicating virtual identity. Similarly, the congruence coefficient between the "g" factors obtained from white and black standardization samples of the WISC battery in the U.S. was .995, and the variance in test scores accounted for by "g" was highly similar for both groups.