The Perry Preschool Project data presented in exercise 10.39 can be divided to see whether there are different effects for males and females. The table shows a summary of the data for males (Schweinhart et al. 2005).

a. Find the graduation rate for males who went to preschool, and compare it with the graduation rate for males who did not go to preschool.

b. Test the hypothesis that preschool and graduation are associated, using a significance level of 0.05.

c. Exercise 10.40 showed an association between preschool and graduation for just the females in this study. Write a sentence or two giving your advice to parents with preschool-eligible children about whether attending preschool is good for their children’s future academic success, based on this data set.

The Perry Preschool Project was created in the early 1960s by David Weikart in Ypsilanti, Michigan. One hundred twenty three African American children were randomly assigned to one of two groups: One group enrolled in the Perry Preschool, and one did not enroll. Follow-up studies were done for decades to answer the research question of whether attendance at preschool had an effect on high school graduation. The table shows whether the students graduated from regular high school or not. Students who received GEDs were counted as not graduating from high school. This table includes 121 of the original 123. This is a test of homogeneity, because the students were randomized into two distinct samples. (Schweinhart et al. 2005)

Preschool No Preschool HS Grad 16 21 HS Grad No 16 18