An educator wants to determine whether early exposure to school will affect IQ. He enlists the aid of the parents of 24 of preschool-age children to participate in this experiment, 12 children go to preschool and 12 children stay home. At the end of 2 years, the IQs of all the children are measured. The results are as follows: IQ
Twins at Twins at
pair pre-school home
1 109 116
2 122 119
3 110 106
4 119 115
5 114 118
6 112 103
7 128 125
8 114 116
9 108 107
10 117 123
11 117 116
12 106 104
Does early exposure to school affect IQ? Use α = 0.052 tail.