a.
Determine the percentage of people who suffered another stroke in each treatment and explain on the basis of these percentages whether the clopidogrel is effective in reducing the risk of recurrent stroke or not.
The
b.
Determine whether the given study is a controlled experiment or an observational study.
c.
Determine the treatment and the response variable of the given study.
d.
Determine the cause and effect of the study on the survival chances of patients and explain why the cause and effect conclusion of the study cannot be drawn.
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INTRODUCTORY STATISTICS (LOOSELEAF)
- What is an experiment?arrow_forwardIn an article about unusual allergies, a doctor explained that allergy to sulfites is usually seen in patients with asthma. The typical reaction is a sudden increase in asthma symptoms after eating a food containing sulfites. Studies are performed to estimate the percentage of the nation's 10 million asthmatics who are allergic to sulfites. In one survey, 22 of 400 randomly selected asthmatics in the country were found to be allergic to sulfites. Find and interpret a 90% confidence interval for the proportion, p, of all asthmatics in the country who are allergic to sulfites. Click here to view page 1 of the table of areas under the standard normal curve. Click here to view page 2 of the table of areas under the standard normal curve. The 90% confidence interval is from to. (Round to three decimal places as needed.) Interpret the confidence interval. Choose the correct answer below. O A. With 90% confidence, the true proportion of all asthmatics in the country who are allergic to…arrow_forwardA double-blind randomized experiment compared the effects of the drug Lorcaserin and a placebo on weight loss in overweight adults. All subjects were also required to undergo diet and exercise counseling. The study involved 1000 participants where half of them would take Lorcaserin and half the placebo. The researchers found that after a year the treatment group had an average weight loss of 5.8 kg while the placebo group had an average weight loss of 3.9 carmona, kg. Based on this information researchers need to decide if Locarserin can be a possible treatment for weight loss. a. What would be a Type I error in this context? Your answer should consist of both the researchers’ decision and what the reality is. b. What would be a Type II error in this context? Your answer should consist of both the researchers’ decision and what the reality is.arrow_forward
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- Most cases of cervical cancer are linked to a few strains of the human papilloma virus (HPV). The pharmaceutical company Merck developed a vaccine (Gardisil) against these HPV strains. Worldwide clinical trials followed young women after vaccination or administration of placebo for two to four years for signs of HPV-caused cervical cancer. Based on a sample of 100 women in the Gardisil group, 24 % developed cervical cancer, and based on a sample of 100 women in the placebo group, 34 % developed cervical cancer. Test the claim that the proportion of women who developed cervical cancer in the Gardisil group is less than the proportion of women who developed cervical cancer in the placebo group at a = 0.10. Round your answers to three decimal places, and round any interim calculations to four decimal places. Fill in the hypotheses below where p₁ denotes the proportion of women who developed cervical cancer in the Gardisil group and P2 denotes the proportion of women who developed cervical…arrow_forwardResearchers studied 208 infants whose brains were temporarily deprived of oxygen due to complications at birth. When researchers detected oxygen deprivation, they randomly assigned babies to either usual care or to a whole-body cooling group. The goal was to see whether reducing body temperature for three days after birth increased the rate of survival without brain damage. What is the explanatory variable? A. Survival without brain damage B.Infants whose brains are temporarily deprived of oxygen C. Usual care or whole-body coolingarrow_forwardMost cases of cervical cancer are linked to a few strains of the human papilloma virus (HPV). The pharmaceutical company Merck developed a vaccine (Gardisil) against these HPV strains. Worldwide clinical trials followed young women after vaccination or administration of placebo for two to four years for signs of HPV-caused cervical cancer. Based on a sample of 100 women in the Gardisil group, 26% developed cervical cancer, and based on a sample of 100 women in the placebo group, 32% developed cervical cancer. Test the claim that the proportion of women who developed cervical cancer in the Gardisil group is less than the proportion of women who developed cervical cancer in the placebo group at a = 0.05. Round your answers to three decimal places, and round any interim calculations to four decimal places. Fill in the hypotheses below where p₁ denotes the proportion of women who developed cervical cancer in the Gardisil group and p2 denotes the proportion of women who developed cervical…arrow_forward
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