Unit 13- Written Assignment 10: MANOVA


Load the data file unit 13_SPSSHW10_data_MANOVA.sav. Geiselman and colleagues (1984) developed the Cognitive Interview (CogInt) to help police officers obtain accurate information from witnesses. Subsequent research has demonstrated that the use of the CogInt results in an increase in recall for the details of an event, however, there is less evidence that the CogInt results in more accurate descriptions of the people involved in the event. A psychologist has developed a new interview, which she calls the “Visual Interview” (VisInt) which is specifically designed to help witness describe the people they saw. A group of 20 participants watched a video of two actors performing a number of actions. After a delay of 24 hours, half the participants were interviewed using the CogInt and half using the VisInt. Each participant’s description of the event (Memory_Events) was scored out of 100 and their description of the actors (Memory _People) was scored out of 60.

  1. Check your data to determine whether it is appropriate for analysis using MANOVA. Report why or why not. Do not forget to check the assumptions. (3 pts)
  2. Run a MANOVA. The psychologist hypothesized that the VisInt would result in better memory for the appearance of the actors. Report the results to this hypothesis. Analyze the data to test this hypothesis. Is one interview type better than the other to use to describe people? (5 pts)
  3. The psychologist hypothesized that there is no difference between the VisInt and CogInt groups for recall of events. Report the results to this hypothesis. (5 pts)
  4. Assuming these results are reliable, what are the implications with regard to how police should interview witnesses? Which interview technique should be used to find out information about people and which one for events? (6 pts)
  5. Save and submit the SPSS syntax and output files used to complete items 1-4 above. The file names should begin with your first and last name followed by the homework number (e.g., John Doe HW9.sps; John Doe HW9.spv). (1 point)