Question

An educator wants to determine if early exposure to school will affect IQ. He enlists the aid of the parents of 10 pairs of preschool-age identical twins who agree to let their twins participate in his experiment. One member of each twin pair is enrolled in preschool for 2 years, while the other member of each pair remains at home. At the end of 2 years, subjects in both conditions were given an intelligence test. The test scores recorded are given below.

Preschool: 110 121 107 117 119 125 130 116 118 110

Home: 95 105 109 120 104 100 128 110 100 93

a. Describe (1) the independent variable and its levels, and (2) the dependent variable and its scale of measurement.

b. Describe the null and alternative hypotheses for the study described.

c. Using Excel, conduct a statistical test of the null hypothesis at p = .05. Be sure to properly state your statistical conclusion.

d. Provide an interpretation of your statistical conclusion in part C.

e. What type of statistical error might you have made in part C?

f. Obtain the 95% confidence interval using the obtained statistic.

g. Provide an interpretation of the confidence interval obtained in part f

. h. Does the confidence interval obtained support your statistical conclusion? Explain your answer

Answer 1