Question

3. A researcher was interested in whether arachnophobia (fear of spiders) is specific to real spiders, or whether pictures of spiders can evoke similar anxiety. Twelve people were exposed to a real spider, and their level of anxiety assessed (high scores correspond to higher anxiety). Twelve additional people were shown a picture of a spider, and their anxiety was also measured. The data are as follows:

Person	Group	Anxiety Score
1	Picture	30
2	Picture	35
3	Picture	45
4	Picture	40
5	Picture	50
6	Picture	35
7	Picture	55
8	Picture	25
9	Picture	30
10	Picture	45
11	Picture	40
12	Picture	50
13	Real Spider	40
14	Real Spider	35
15	Real Spider	50
16	Real Spider	55
17	Real Spider	65
18	Real Spider	55
19	Real Spider	50
20	Real Spider	35
21	Real Spider	30
22	Real Spider	50
23	Real Spider	60
24	Real Spider	39

Carry out a hypothesis test to assess whether the mean anxiety level of individuals who encounter a real spider differs from those who are shown a picture of a spider. Use a two-tailed test with alpha = .05. You may do this "by hand" or by using SPSS. Show all four steps of the hypothesis test.

Answer 1

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