No Variation in a Sample An experiment was conducted to test the effects of alcohol. Re-searchers measured the breath alcohol levels for a treatment group of people who drank ethanol and another group given a placebo. The results are given below (based on data from “Effects of Alcohol Intoxication on Risk Taking, Strategy, and Error Rate in Visuomotor Performance,” by Streufert et al.. Journal of Applied Psychology, Vol. 77, No. 4). Use a 0.05 significance level to test the claim that the two sample groups come from populations with the same mean.
Treatment Group: n1 = 22,
Placebo Group: n2 = 22,
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Student's Solutions Manual To Accompany Elementary Statistics Tenth Edition
- Evans conducted a study to determine if the frequency and characteristics of pediatric problems in elderly patients with diabetes present differences with respect to patients of the same age, but without diabetes. The individuals studied, interned in a clinic, were between 70 and 90 years old. Among the researchers' findings are the following statistics. with respect to the scores on the deep tendon reflexes meters:Sample without Diabetes: 79 / 2.1 / 1.1With Diabetes: 74 / 1.6 / 1.2Is it possible to conclude, based on the data, that, on average, diabetic patients they have reduced deep tendon reflexes in comparison with patients without diabetes of the same age?arrow_forwardIs injecting medical cement effective in reducing pain for people who have suffered fractured vertebrae? A paper describes an experiment to compare patients who underwent vertebroplasty (the injection of cement) to patients in a placebo group who underwent a fake procedure. Because the placebo procedure was similar to the vertebroplasty procedure except for the actual injection of cement, patients participating in the experiment were not aware of which treatment they received. All patients were asked to rate their pain at three different times—3 days, 14 days, and 1 month after the procedure. Summary statistics are given in the accompanying table. Pain Intensity VertebroplastyGroup Placebo Group n = 73 n = 76 mean sd mean sd 3 days 4.2 2.8 3.9 2.9 14 days 4.3 2.9 4.5 2.8 1 month 3.9 2.9 4.6 3.0 (a) Construct a 95% confidence interval for the difference in mean pain intensity between the two treatments at 14 days after treatment. (Use ?Vertebroplasty −…arrow_forwardThe table below summarizes a data set we first encountered in Exercise 6.29 that examines the responses of a random sample of college graduates and nongraduates on the topic of oil drilling. Complete a chi-square test for these data to check whether there is a statistically significant difference in responses from college graduates and non-graduates. χ2:? df:? Conclusion: There is insufficient evidence that there is an association between support for off-shore drilling and having a college degree There is strong evidence that the proportion of those supporting off-shore drilling is greater than those having a college degree There is insufficient evidence that the proportion of those supporting off-shore drilling is greater than those having a college degree There is strong evidence that there is an association between support for off-shore drilling and having a college degreearrow_forward
- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill