In: Statistics and Probability
Stat212 Statistical II B Spring 2020 Midterm 2 Name:
SHOW YOUR WORK TO EARN FULL CREDIT
1. (20 points) Susan Sound predicts that students will learn most effectively with a constant background sound, as opposed to an unpredictable sound. She randomly divides 15 students into 2 groups of 7 and 8 each. All students study a passage of text for 30 minutes. Those in group 1 study with background sound at a constant volume in the background. Those in group 2 study with noise that changes volume periodically. After studying, all students take a 10 point multiple choice test over the material. Their scores have the following test statistics.
Group Constant sound Random sound
Sample size Mean Variance
8 6 4.86
7 4 2.86
Construct the F statistic ANOVA table using data. Stat the hypotheses for ANIVA and use significance level 0.05 to test your hypotheses. What is the p-value of the test?
Explain whether you use can conclusion above to support Susan’s prediction or not? Explain why and how.