Preliminary data analyses indicate that you can reasonably apply the z-interval procedure (Procedure 8.1 on page 339) in Exercises 8.69–8.74.
8.73 Political Prisoners. A. Elders et al. studied various characteristics of political prisoners from the former East Germany and presented their findings in the paper “Posttraumatic Stress Disorder (PTSD) Following Political Imprisonment: The Role of Mental Defeat, Alienation, and Perceived Permanent Change” (Journal of Abnormal Psychology, Vol. 109. pp. 45–55). According to the article, the mean duration of imprisonment for 32 patients with chronic PTSD was 33.4 mouths. Assuming that σ = 42 months, determine a 95% confidence interval for the mean duration of imprisonment, μ, of all East German political prisoners with chronic PTSD. Interpret your answer in words.
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Introductory Statistics (10th Edition)
- Recent research indicates that the effectiveness of anti-depressant medication is directly related to the severity of the depression (Khan, Brodhead. Kolts, and Brown, 2005). Based on pre-treatment dcprcssion scores, paticnts werc divlded into four groups based on their level of depi ession. After receiving the antidepression medication, depi ession scores were measured again and the amount of improvement was recorded for cach pcrsion. The following data are similar to the results of the study. Moderately High Moderate Moderate Low Severe Severe 4 5 N= 16 2 3 6 6 G= 48 +a 2 2. 2 6 ΣΧ- 2 4 M=2.5 M=2 M=4 M-5 T= 10 T= 8 T= 16 T=20 SS=. .. SS=2 SS=8 SS- 6 A, Complete the places marking by ... and answer the question whether the data indicate significant difference among the four levels of severity? Test with a= 0.05. B, Compute n', the percentage of variance expressed by group difference.arrow_forwardA park ranger takes a sample of 15 national park patrons and measures their attitudes about a new park to make inferences about national park patrons in general. What is the population that the park ranger is interested in studying? When the park ranger has computed the sample’s average attitude score, is this a statistic or a parameter? Why?arrow_forwardA sociologist wants to investigate the question, "Is there a relationship between texting during class and grade-point-average (GPA) among high school seniors in a large district?" Which study design is most appropriate? Before the semester starts, randomly select 40 seniors from each high school who do not text during class. Assign 20 to the texting treatment group (text three or more times during every class meeting) and 20 to the control group (no texting during class). At the end of the semester, obtain each student’s GPA from the appropriate admissions and records office. Compare the GPA of students who routinely text during class to the GPA of students who do not text during class. Before the semester starts, randomly select 40 seniors from each high school who do not text during class. Assign 20 to the texting treatment group (text three or more times during every class meeting) and 20 to the control group (no texting during class). At the end of the semester,…arrow_forward
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- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw HillBig Ideas Math A Bridge To Success Algebra 1: Stu...AlgebraISBN:9781680331141Author:HOUGHTON MIFFLIN HARCOURTPublisher:Houghton Mifflin Harcourt