Question

Heart rate during laughter. Laughter is often called “the best medicine,” since studies have shown that laughter can reduce muscle tension and increase oxygenation of the blood. In the International Journal of Obesity (Jan. 2007), researchers at Vanderbilt University investigated the physiological changes that accompany laughter. Ninety subjects (18–34 years old) watched film clips designed to evoke laughter. During the laughing period, the researchers measured the heart rate (beats per minute) of each subject,
with the following summary results:

• Mean = 73.5,
• Standard Deviation = 6.
• n = 90 (we can treat this as a large sample and use z)

It is well known that the mean resting heart rate of adults is 71 beats per minute.

1) Construct 95% Confidence interval using z-value. What is the upper bound of CI?

Use 4 significant decimal places for your answer, and use the proper rules of rounding. I am looking for just the answer, not the equation.

2) Construct 95% Confidence interval using z value. What is the lower bound of CI?

Use 4 significant decimal places for your answer, and use the proper rules of rounding. I am looking for just the answer, not the equation.

3) Calculate the value of the test statistic.(z*)

Use 4 significant decimal places for your answer, and use the proper rules of rounding. I am looking for just the answer, not the equation.

4) If alpha = 05, find the critical value of the rejection region for this test.   Use three decimal places and use the proper rules of rounding.

5) What is your conclusion in regards to the Null Hypothesis?

a) Fail to reject Ho

b) Reject Ho

Answer 1