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STAT/167 Statistics for the Life Sciences
University of Phoenix Material
Hypothesis Testing and Correlation Worksheet
Answer the following questions. For questions requiring material from Statdisk, make sure to turn
labels on, take a screen capture (CTRL-Print Screen on most Windows-based computers), and
paste the image into the worksheet. Crop the image as appropriate.
For questions 1-4, please respond in a paragraph of no more than 100 words for each question.
1. What is a hypothesis? What is a hypothesis test (0.5 point)?
2. What is a null hypothesis? What is an alternative hypothesis (0.5 point)?
3. What is a test statistic (0.5 point)?
4. What are significance levels (0.5 point)?
5. Complete this table contrasting the traditional, p-value, and confidence interval methods of
testing a claim about a proportion (1 point).
Traditional p-value Confidence Interval
How would you use
this method?
Why would you use
this method?
What is an
example of when
this would be used
in life sciences
research?
Use the following description and table to answer questions 6-10.
A pharmaceutical company wants to determine if there is a significant reduction in heart rate with
their new drug, Clardozan, at the .01 level of significance. The researchers took a random sample
of 30 adults and randomly selected each to receive either Clardozan or the placebo. Heart rates
for each subject and treatment group are presented below; assume data are normally distributed
with equal variances.
Subject Clardozan Subject Placebo
Heart Rate Heart Rate
1 81 2 78
4 60 3 88
7 91 5 63
8 103 6 56
10 85 9 70
13 88 11 77
Adapted from Biostatistics for the Biological and Health Sciences faculty materials with permission from Pearson Addison-
Wesley.
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STAT/167 Statistics for the Life Sciences
14 84 12 64
16 60 15 48
17 60 18 51
19 72 20 52
23 96 21 76
24 75 22 80
26 58 25 51
29 70 27 66
30 81 28 55
6. What is the independent variable? What is the dependent variable? Why (0.5 point)?
7. What is the null hypothesis? What is the alternative hypothesis? Is this a one-tailed or a two-
tailed test (0.5 point)?
8. What test statistic will you use? Why (0.5 point)?
9. What is the critical value? What is the value of the test statistic (0.5 point)?
10. Would you accept or reject the null hypothesis? Explain your conclusion in a 100- to 150-
word summary (0.5 point).
Use the following description and table to answer questions 11-14.
More men than women were randomly assigned to the Clardozan group. After a careful
examination of the results, the pharmaceutical company wonders if gender influenced the results.
Conduct a test to determine if there was a relationship between gender and group assignment
using the .05 level of significance. The 2 x 2 contingency table presented below shows subject
assignment by treatment group and by gender.
Male Female
Clardozan 9 6
Placebo 7 8
11. What is the null hypothesis? What is the alternative hypothesis? Is this a one-tailed or a two-
tailed test (0.5 point)?
12. What test statistic will you use? Why (0.5 point)?
13. What is the critical value? What is the value of the test statistic (0.5 point)?
14. Would you accept or reject the null hypothesis? Explain your conclusion in a 100- to 150-
word summary (0.5 point).
15. What is the F distribution? Describe it in no more than 100 words (0.5 point).
16. How and when do researchers use the F distribution? Explain in no more than 150 words (0.5
point).
17. What does it mean if F = 1.0251? Explain in no more than 150 words (0.5 point).
Use the following information to answer questions 18-19. Using Data Set 1 in Appendix B of the
text (Data Set: Health Exam Results, Female Health, Part I in Statdisk), determine the correlation
between women’s age and women’s weight.
18. Calculate r using Statdisk. Paste the Correlation and Regression report into your response.
What is r (0.5 point)?
Adapted from Biostatistics for the Biological and Health Sciences faculty materials with permission from Pearson Addison-
Wesley.
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19. Interpret r and r . Explain whether there is a significant correlation between women’s age and
women’s weight at the 0.05 significance level, and explain how much of the variation in
women’s weight is explained by its linear association with women’s age (0.5 point).
Adapted from Biostatistics for the Biological and Health Sciences faculty materials with permission from Pearson Addison-
Wesley.
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