IQ scores are measured from 30 children who A. participated in Head Start and from 32 otherwise CO comparable children who did not participate in Head the Start. The mean for the Head Start group is 103, the mean for the No Head Start Group is 95, and the cor standard error of the difference between the means is 1 4. Does Head Start have a significant effect on IQ? 10 Would a correlated (repeated measures) test be used or a test for independent groups? 19 2 The critical value at 0.05 for a directional test is 1.671