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)
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- In order to investigate a claim that the average time required for the county fire department to respond to a reported fire is greater than 15 minutes, county staff determined the response times for 40 randomly selected fire reports. The data was used to test H0H0: μ = 15 versus HaHa: μ > 15 and the computed P‐value was 0.12. If a 0.05 level of significance is used, what conclusions can be drawn? There is convincing evidence that the mean response time is 15 minutes (or less). There is convincing evidence that the mean response time is greater than 15 minutes. There is not convincing evidence that the mean response time is greater than 15 minutes.arrow_forwardThe article “Well-Fed Crickets Bowl Maidens Over” (Nature Science Update, February 11, 1999) reported that female field crickets are attracted to males with high chirp rates and hypothesized that chirp rate is related to nutritional status. The usual chirp rate for male field crickets was reported to vary around a mean of 60 chirps per second. To investigate whether the chirp rate was related to nutritional status, investigators fed 22 male crickets a high protein diet for 8 days, after which chirp rate was measured. Let: The parameter μμ be the mean chirp rateof male crickets on a high protein diet for 8 days. Given: The mean chirp rate for the random sample of crickets on the high protein diet was reported to be 65.32 chirps per second with a standard deviation of 12. Research Question: Is there convincing evidence that the mean chirp rate for crickets on a high protein diet implies an advantage in attracting the ladies? It is known that the researchers did not want to…arrow_forwardThe article “Well-Fed Crickets Bowl Maidens Over” (Nature Science Update, February 11, 1999) reported that female field crickets are attracted to males with high chirp rates and hypothesized that chirp rate is related to nutritional status. The usual chirp rate for male field crickets was reported to vary around a mean of 60 chirps per second. To investigate whether the chirp rate was related to nutritional status, investigators fed 22 male crickets a high protein diet for 8 days, after which chirp rate was measured. Let: The parameter μμ be the mean chirp rateof male crickets on a high protein diet for 8 days. Given: The mean chirp rate for the random sample of crickets on the high protein diet was reported to be 65.32 chirps per second with a standard deviation of 12. Research Question: Is there convincing evidence that the mean chirp rate for crickets on a high protein diet implies an advantage in attracting the ladies? It is known that the researchers did not want to…arrow_forward
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