Results for a 1997 survey of about 25,000 each male and female nonfarm wage and salary workers were published in the Monthly Labor Review in 1998. Hours worked in the week prior to the survey were found to have mean and standard deviation 42.66 and 12.46 for the men, 36.90 and 11.93 for the women. The test statistic turns out to be larger in absolute value for the women than it is for the men. Is this because the women’s sample mean 36.90 is further from 40 than 42.66 is, or because the women’s standard deviation 11.93 is smaller than the men’s, or both of these, or neither of these?

Results for a 1997 survey of about 25,000 each male and female nonfarm wage and salary workers were published in the Monthly Labor Review in 1998. Hours worked in the week prior to the survey were found to have mean and standard deviation 42.66 and 12.46 for the men, 36.90 and 11.93 for the women. The test statistic turns out to be larger in absolute value for the women than it is for the men. Is this because the women’s sample mean 36.90 is further from 40 than 42.66 is, or because the women’s standard deviation 11.93 is smaller than the men’s, or both of these, or neither of these?