Suppose that a researcher, using wage data on 250 randomly selected male workers and 280 female workers, estimates the OLS regression,

(0.18)(0.84)

Figures in the parentheses represent standard errors.

Where Wage is measured in $/hour is a binary variable that is equal to one if the person is a male and 0 if the person is a female. Define the wage gender gap as the difference in mean earnings between men and women.

1. Is the estimated gender gap significantly different from zero? Conduct a test for this.
2. Construct a 95% confidence interval for the gender gap.