Chapter 10.3, Problem 1LC

An educational psychologist would like to determine whether access to computers has an effect on grades for high school students. One group of n = 16 students has home room each day in a computer classroom in which each student has a computer. A comparison group of n = 16 students has home room in a traditional classroom. At the end of the school year, the average grade is recorded for each student. The data are as follows:

  

a. Is there a significant difference between the two groups? Use a two-tailed test with a = .05.

b. Compute Cohen’s d to measure the size of the difference.

c. Write a sentence that demonstrates how the outcome of the hypothesis test and the measure of effect size would appear in a research report.

d. Compute the 90% confidence interval for the population mean difference between a computer classroom and a regular classroom.