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To study the long-term effects of preschool programs for poor children, researchers designed an experiment. They recruited 123children who had never attended preschool from low-income families in Michigan. Researchers randomly assigned 62of the children to attend preschool (paid for by the study budget) and the other 61to serve as a control group who would not go to preschool. One response variable of interest was the need for social services for adults. In the past 10years, 38children in the preschool group and 49 in the control group have needed social services.4 1. Does this study provide convincing evidence that preschool reduces the later need for social services? Carry out an appropriate test to help answer this question.

Short Answer

Expert verified

From the given information, the probability is0.2061

Step by step solution

01

Given Information

It is given in the question that, from the previous exercise

Mean(p^1p^2)=0.10

Standard deviation(p^1p^2)=0.097

Does this study provide convincing evidence that preschool reduces the later need for social services?

02

Explanation

The probability thatp^1p^2is less than or equal to0.02can be computed as:

localid="1650435144025" P(p^1p^20.02)=P((p^1p^2)(p1p2)(p^1p^2)0.02(p1p2)(p^1p^2))=P(Z0.02(0.1)0.097)=P(Z>0.82)=0.2061

Therefore, the required probability is 0.2061

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