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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 61 to serve as a control group who would not go to preschool. One response variable of interest was the need for social services as adults. In the past 10years, 38children in the preschool group and 49in the control group have needed social services.

The Minitab output below gives a 95% con铿乨ence interval for p1-p2. Interpret this interval in context. Then explain what additional information the con铿乨ence interval provides.

Short Answer

Expert verified

From the given information, here, 0does not lie in the computed confidence interval. Thus, it could be said that there is a difference in the two population proportions.

Step by step solution

01

Given Information

It is given in the question that,

02

Explanation

From the overhead output, the 95% confidence interval for the difference in population proportions is (0.0333680,0.347383). It hints that there is a 95% chance that the dissimilarity in population proportion lies between 0.0333680and 0.347383

Here, 0does not lie in the computed confidence interval. Thus, it could be said that there is a difference in the two population proportions.

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Most popular questions from this chapter

46. Happy customers As the Hispanic population in the United States has grown, businesses have tried to understand what Hispanics like. One study inter-viewed a random sample of customers leaving a bank. Customers were classified as Hispanic if they preferred to be interviewed in Spanish or as Anglo if they preferred English. Each customer rated the importance
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Dr Teresa Amabile conducted a study involving 47college students, who were randomly assigned to two treatment groups. The 23students in one group were given a list of statements about external reasons (E) for writing, such as public recognition, making money, or pleasing their parents. The 24students in the other group were given a list of statements about internal reasons (I) for writing, such as expressing yourself and enjoying playing with words. Both groups were then instructed to write a poem about laughter. Each student鈥檚 poem was rated separately by 12different poets using a creativity scale. The 12poets鈥 ratings of each student鈥檚 poem were averaged to obtain an overall creativity score. We used Fathom software to randomly reassign the 47subjects to the two groups 1000times, assuming the treatment received doesn鈥檛 affect each individual鈥檚 average creativity rating. The dot plot shows the approximate randomization distribution of x1-xE

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Acupuncture
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