In your submitted report, you should perform the appropriate analyses and describe the different steps of the analyses, as described below. To present your analyses and conclusions you should write a brief introduction, detailed results section, and a concise discussion section, using the same format that would be expected in a journal article (i.e., APA style). There is an 1800-word limit for this assignment. Independent of the word limit, you may include a maximum of four tables and/or figures. Appendices are not permitted. References are not required but can be included to justify specific analytic decisions (these will not be included in the word count). Data set These data (perceptualstates.sav) come from a study in which patients with temporal lobe epilepsy completed a 25-item checklist (see next page) regarding different types of perceptual distortions designed to cover the range of aberrant perceptual states these patients may experience. Participants rated how frequently they have the different perceptual experiences (1 = “never” to 5 – “very often”). The researchers are interested in how these data can be used to identify different perceptual distortions in this population.
Please perform a factor analysis (FA)/principal components analysis (PCA) on these data. In your write-up: (a) provide a brief introduction (5 marks); (b) detail the screening that was performed to ensure the data were suitable for FA/PCA (10 marks); (c) justify the type of FA/PCA you used (10 marks); (d) justify the type of rotational method you used (10 marks); (e) determine whether all the items should be retained in the analyses and rerun analyses and re-present the results after eliminating any items you did not retain (15 marks); (f) present the results of the analysis that best uncovers the structure of the experiences measured, including how many factors/components should be extracted (20 marks); (g) interpret and label the factors/components identified in the analysis (10 marks); (h) extract factor scores for each participant based on the final solution and explain your choice of method (10 marks); and (i) present a brief discussion of the results (5 marks). All features of the report should be written according to APA style (5 marks).
1. I hear voices when no one else is present.
2. My arms appear larger than normal.
3. My perception of time is accurate.
4. It seems like the space around me is shaking.
5. My vision is very good. 6. My experience of my body is accurate.
7. I have difficulty distinguishing left from right.
8. My body feels as though it’s not my own.
9. I think things are closer than they actually are.
10. I hear familiar sounds when listening to static noise.
11. I feel that my hands belong to someone else.
12. I am good at keeping track of time.
13. I can easily discriminate imagination from reality.
14. Hours and hours will appear to go by in only a few minutes.
15. I misperceive the location of people with whom I’m speaking.
16. I see colours when none are present.
17. I feel as though I’m floating out of my body.
18. My hearing is normal.
19. Time feels very fragmented.
20. I see things that others don’t see.
21. I am unsure where my body ends.
22. I can easily distinguish different periods of time.
23. The space around me feels very tight.
24. I recognize my body in the mirror.
25. I feel detached from my body.