case study Do Pets or Friends Help Reduce Stress? If you are a dog lover, having your dog with you may reduce your stress level. Does having a friend with you reduce stress? To examine the effect of pets and friends in stressful situations, researchers recruited 45 women who said they were dog lovers. Fifteen women were assigned at random to each of three groups: to do a stressful task alone, with a good friend present, or with their dogs present. The stressful task was to count backward by 13s or 17s. The woman's average heart rate during the task was one measure of the effect of stress. The table below shows the data.! Average heart rates during stress with a pet (P), with a friend (F), and for the control group (C) GROUP RATE GROUP RATE GROUP RATE GROUP 69.169 P 68.862 84.738 75.477 F 99.692 87.231 C 84.877 62.646 P 70.169 P 64.169 58.692 P 70.077 80.369 91.754 79.662 F 88.015 C 87.446 87.785 69.231 F 81.600 75.985 F 91.354 73.277 F 86.985 83.400 F 100.877 84.523 F 92.492 F 102.154 C 77.800 70.877 P 86.446 97.538 F 89.815 65.446 F 80.277 P 85.000 F 98.200 90.015 101.062 F 76.908 99.046 97.046 69.538 RATE P C P C F 72.262 P F F Refer to the chapter-opening Case Study (page 1). You will now use what you I have learned in this chapter to analyze the data. 1. 2. 3. Construct an appropriate graph for comparing the heart rates of the women in the three groups. Calculate numerical summaries for each group's data. Which mea- sures of center and spread would you choose to compare? Why? Determine if there are any outliers in each of the three groups. Show your work. Write a few sentences comparing the distributions of heart rates for the women in the three groups. Based on the data, does it appear that the presence of a pet or friend reduces heart rate during a stressful task? Justify your answer. 4. 5