MATH 3070: Worksheet No.7
NAME:
1. Answer the following questions regarding the study in Exercise 6.4. (Data file: Chapter 6/ex6-4.csv)
(a) Present a short description of the study and the data, including summary statistics for each
variable.
(b) Present the comparison of the two groups in boxplot, and comment on the data based on the
visualization.
(c) Do the data provide sufficient evidence that rats exposed to a cold environment have a
higher blood pressure than rats exposed to a normal environment? Construct the null and the
alternative hypothesis for the test.
(d) Calculate the test statistic and the p-value of the test.
(e) Choose the significance level, and interpret your findings.
(f) Construct a 95% confidence interval for the difference in the two population means.
2. Answer the following questions regarding the study in Exercise 6.5. (Data file: Chapter 6/ex6-5.csv)
(a) Present a short description of the study and the data, including summary statistics for each
variable.
(b) Present the comparison of the two groups in boxplot. Then comment on the data based on
the visualization.
(c) Do the data provide sufficient evidence to indicate a difference in mean oxygen content
between locations above and below the town? Construct the null and the alternative
hypothesis for the test.
(d) Construct QQ normal plot for each group. Do the normality assumption for the t-test appear
to be valid for this study?
(e) Calculate the test statistic and the p-value of the test.
(f) Choose the significance level, and interpret your findings.
(g) How large is the difference between the mean oxygen content above and below the town?
3. Answer the following questions regarding the study in Exercise 6.16. (Data file: Chapter 6/ex6-
16.csv)
(a) Present a short description of the study and the data, including summary statistics for each
variable.
