Educational Technology Inc. sells software to provide guided homework problems for a statistics course. The company would like to know if students who use the software score better on exams. A sample of students who used the software had the following exam scores: 86, 78, 66, 83, 84, 81, 84, 109, 65, and 102. Students who did not use the software had the following exam scores: 91, 71, 75, 76, 87, 79, 73, 76, 79, 78, 87, 90, 76, and 72. Assume the population standard deviations are not the same. At the alpha = .10 significance level, can we conclude that there is a difference in the mean scores for the two groups of students
a. What are the three assumptions for CASE C?
b. State the null and alternative hypothesis for this problem.
c. State the level of significance for this problem.
d. Which distribution (normal or t) should be used in this problem? Explain why.
e. Create a decision rule for this problem. Include the critical value. (USE TEXTBOOK TABLE.) Make sure it agrees with the excel printout.
f. Calculate the test statistic. (BY HAND). Make sure it agrees with the excel printout.
g. What is your conclusion? EXPLAIN IN DETAIL.
h. Estimate the p-value for this problem. Restate the conclusion. What is the actual p-value from the excel printout?