Question

Research Scenario: A clinical psychologist is studying whether aerobic exercise improves anxiety in veterans diagnosed with PTSD. Participants agreed to take an anxiety measure before and after a 4 week aerobic exercise plan (5 workouts per week for four weeks). The values provided in the table are anxiety scores (scale measurement) collected before and after the aerobic exercise sessions, with higher numbers indicating higher anxiety. Using this table, enter the data into a new SPSS data file and run a correlated groups t test to test whether aerobic exercise improves anxiety in veterans with PTSD. Remember to name and define your variables under the “Variable View,” then return to the “Data View” to enter and analyze the data. Remember, data will be entered differently than “normal” since this is a within subjects design. You will have two columns – “Before” and “After”, and the numbers will be your dependent variable (anxiety scores).

=

Before	After
24	19
23	23
22	17
30	19
31	22
30	13
38	35
25	24
33	28
38	35

1. Paste relevant SPSS output. (2 pts)

2.     Create an appropriate graph to display this data. Make sure you have a y axis label. (2 pts)

3. Write an APA-style Results section based on your analysis. All homework “Results sections” should follow the examples provided in the presentations and textbooks. They should include the statistical statement within a complete sentence that mentions the type of test conducted, whether the test was significant, and if relevant, the effect size. Don’t forget to include a decision about the null hypothesis. (3 pts)

Before	After
24	19
23	23
22	17
30	19
31	22
30	13
38	35
25	24
33	28
38	35

Answer 1

NULL HYPOTHESIS H0:

ALTERNATIVE HYPOTHESIS Ha:

LEVEL OF SIGNIFICANCE =0.05

test statistic= -3.637

degrees of freedom= 9

P value= 0.005/2= 0.0025 (For one tailed test)

Since P value SMALLER THAN 0.05 THEREFORE SIGNIFICANT

DECISION: REJECT NULL HYPOTHESIS H0.

CONCLUSION: WE HAVE SUFFICIENT EVIDENCE TO CONCLUDE THAT THE aerobic exercise improves anxiety in veterans diagnosed with PTSD.

This is scatterd plot for Before and After data.