On the existence of sex, menstrual-cycle, and race differences in psychoacoustical performance

Performance was measured on several common psychoacoustical tasks for about 70 subjects. Subjects were tested in same-sex crews of 4—8 members. Testing required 8—10 weeks for each crew to assure that all subjects were well practiced on all tasks. Of initial interest were any differences by sex and by menstrual cycle. Correlation and effect size were the primary measures of interest. Resampling was used to determine implied significance for the various comparisons studied. During analysis, racial background turned out to be a relevant variable; because this was unexpected, recruitment by, and documentation of, race was poor, so the best we could do was categorize subjects as Non-White or White. For essentially all of the psychoacoustical tasks measured, the sex and menstrual differences were non-significant when the results were pooled across race. However, when the subjects were partitioned by race, small-to-moderate sex and menstrual differences did emerge, primarily for the White subjects. Correlations...