In Problems 22–31, for each study, explain which statistical procedure (estimating a single proportion; estimating a single mean; hypothesis test for a single proportion; hypothesis test for a single mean; hypothesis test or estimation of two proportions, hypothesis test or estimation of two means, dependent or independent) would most likely be used for the research objective given. Assume all model requirements for conducting the appropriate procedure have been satisfied.
28. Does turmeric (an antioxidant that can be added to foods) help with depression? Researchers randomly assigned 200 adult women who were clinically depressed to two groups. Group 1 had turmeric added to their regular diet for one week; group 2 had no additives in their diet. At the end of one week, the change in their scores on the Beck Depression Inventory was compared.
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- The director of marketing at Vanguard Corporation believes that sales of the company's Bright Side laundry detergent (S) are related to Vanguard's own advertising expenditures (A), as well as the combined advertising expenditures of its three biggest rival detergents (R).The marketing director collects 36 weekly observations on S, A, and R . Vanguard's marketing director is comfortable using parameter estimates that are statistically significant at the 10 percent level or better. Give the specific statistical tool that can be used to this problem.arrow_forward1. The data in Table 7–6 were collected in a clinical trial to evaluate a new compound designed to improve wound healing in trauma patients. The new compound was com- pared against a placebo. After treatment for 5 days with the new compound or placebo, the extent of wound healing was measured. Is there a difference in the extent of wound healing between the treatments? (Hint: Are treatment and the percent wound healing independent?) Run the appropriate test at a 5% level of significance. Use the data in Problem 1. Pool the data across the treatments into one sample of size n = 250. Use the pooled data to test whether the distribution of the percent wound healing is approximately normal. Specifically, use the following distribution 30%, 40%, 20%, and 10% and a = 0.05 to run the appropriate test. Percent Wound Healing Treatment 0-25% 26-50% 51-75% 76-100% New compound (n=125) 15 37 32 41 Placebo (n=125) 36 45 34 10arrow_forwardwhich of the following individuals is likely to be excluded from a clinical trial? a-individual with other diseases besides the disease of interest b-an individual whose data is considered to be an outlier c-an individual of who is considered to be a minority d-an individual who will have difficulty complying trial protocols.arrow_forward
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