HW12
Description
A professor is interested in examining how deep breathing can influence feelings of anxiety. She recruits participants in her class right before the final exam, when their feelings of anxiety would be high. She measures their current levels of anxiety, instructs them to engage in 2 minutes of deep breathing, and then measures their anxiety again after they’ve completed the breathing. Below are the anxiety levels of each student before and after deep breathing. Your job is to determine if their anxiety levels significantly DECREASE after deep breathing.
| Before Deep Breathing | After Deep Breathing |
| 17 | 11 |
| 12 | 10 |
| 10 | 4 |
| 12 | 8 |
| 11 | 5 |
| 16 | 4 |
| 8 | 6 |
| 13 | 10 |
1: What’s the null hypothesis for this research question?
Group of answer choices
Ha: Anxiety levels are significantly lower after deep breathing
Ho: Anxiety levels before deep breathing ≤ anxiety levels after deep breathing
2: What’s the alternative hypothesis for this research question?
Group of answer choices
Ha: Anxiety levels are significantly lower after deep breathing
Ho: Anxiety levels are the same before and after deep breathing
3: What’s the best statistical test to use to analyze this research question?
Group of answer choices
Correlation coefficient
F statistic
Independent sample t-test
One sample z-test
One way ANOVA
Dependent samples t-test
4: The next step is to compute the test statistic. What is the t-statistic value (make sure you’re using the t-test formula for the dependent samples t-test). Round your answer to two decimal places.
5: What are the degrees of freedom?
6: Should you do a one-tailed or two-tailed test here? Think about whether the hypothesis is directional or non-directional!
Group of answer choices
two tailed
one tailed
7: What is the critical value?
8: Based on the t-value provided and the critical value, what is your decision about this research study?
Group of answer choices
There is not a significant decrease in anxiety before and after deep breathing.
There is a significant increase in anxiety after deep breathing
There is a significant decrease in anxiety after deep breathing
9: Write up your results as you would see them in an APA style write up. Don’t forget to include your means and sds for the before and after data!
