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Tim is interested in studying whether Cognitive Behavioural Therapy (CBT) is an effective treatment for Obsessive Compulsive Disorder (OCD). Six people who were diagnosed with OCD participated in Tim's study, where he recorded the number of times they washed their hands per day for one month. They were then given a three week intensive CBT program before their hand-washing was monitored for another month. The average number of times per day each participant washed their hands over the two months of observation are as follows:
Participant
Month 1
Month 2
1
11
6
2
8
5
3
14
17
4
10
10
5
22
11
6
15
10
Compute the appropriate statistic to determine whether the program was effective and use this information to fill in the blanks:Q1. revealed that the number of times per day participants washed their hands following the CBT program was Q2. compared to the number of times per day participants washed their hands before the program, Q3. = Q4. , Q5. .Based on the results of this experiment, we should Q6. .
Possible answers for Q1:
a) A single sample t-test
b) A single sample z-test
c) An independent groups t-test
d) A repeated measures t-testPossible answers for Q2:
a) significantly higher
b) significantly lower
c) not significantly different
d) slightly higherPossible answers for Q3:
a) t(4)
b) t(5)
c) t(10)
d) t(11)Possible answers for Q4:
a) 1.31
b) 0.37
c) 4.37
d) 1.78Possible answers for Q5:
A) p < .05
B) p = .05
C) ns
D) p < .01Possible answers for Q6:
a) reject the null hypothesis
b) retain the null hypothesis
c) reject the alternative hypothesis
d) retain the alternative hypothesis
Given data:
Participant |
Month 1 |
Month 2 |
1 |
11 |
6 |
2 |
8 |
5 |
3 |
14 |
17 |
4 |
10 |
10 |
5 |
22 |
11 |
6 |
15 |
10 |
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