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A clinical trial is conducted comparing a new pain reliever for arthritis to a placebo. Participants are randomly assigned to receive the new treatment or a placebo and the outcome is pain relief within 30 minutes. Of the 200 participants who received the new medication, 75 reported pain relief, while 60 out of the 200 participants who received the placebo reported pain relief. Is there a significant difference in the proportions of patients reporting pain relief? Run the test at a 5% level of significance. Give each of the following to receive full credit: 1) the appropriate null and alternative hypotheses; 2) the appropriate test; 3) the decision rule; 4) the calculation of the test statistic; and 5) your conclusion including a comparison to alpha or the critical value.
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- Two different blood pressure medicines are being compared to determine if the average reduction in blood pressure is the same for each medication. The goal of the study is to determine if the medications differ. Twenty men age 50-60 years old are selected for the study. Ten men are chosen at random to receive the first medication and the other 10 men receive the second medication. Each of the 20 men is monitored for one month to determine the change in blood pressure over that time. Minitab provides the 95% confidence interval for (mu1 - mu2) (2.63, 14.18) a. Interpret this 95% CI. b. What assumptions (be specific) are necessary to construct this CI?arrow_forwardMichelle, a student studying music, randomly sampled fellow music majors and asked whether they listen to music while they study. The resulting confidence interval for the proportion of music students who listen to music while studying is (0.09, 0.26). What is the margin of error?arrow_forwardIn a 2005 study 2205 adolescents aged 12 - 19 years old were give a treadmill test to check their cardiovascular health. 750 of the subjects were determined to have poor cardiovascular fitness. The researchers want to claim that more than 30% of adolescents have poor cardiovascular health (with a 5% level of significance). The research hypothesis is Ha : p > 0.30. Complete the test by computing the test statistic, the p-value, and stating your conclusions.arrow_forward
- A small pilot study is conducted to investigate the effect of a nutritional supplement on total body weight. Six participants agree to take the nutritional supplement. To assess its effect on body weight, weights are measured before starting the supplementation and then after 6 weeks. The data are shown below. Is there a significant increase in body weight following supplementation? Run the test at a 5% level of significance. Demonstrate the five steps for hypothesis testing and explain your results. Subject Initial Weight Weight after 6 Weeks 1 155 157 2 142 145 3 176 180 4 180 175 5 210 209 6 125 126arrow_forwardSupport for the U.S. death penalty for convicted murderers was 63% in 2014 (Gallup poll results 2018). In a recent survey of 150 randomly selected U.S. adults, 75 said they were in favor of the death penalty for those convicted of murder. Does this sample appear to come from a population with a lower proportion in favor of the death penalty? d) Say that a = 0.05, what does this mean. Explain in the context of the problem. e) What would it mean to make a type II error? Explain in the context of this problem. f) Use a 0.05 significance level to test the claim. State your conclusion AND interpret your results.arrow_forwardColor blindness, or dyschromatopsia, is a form of genetic deficiency in color perception. The condition is much more prevalent among males than females, pointing to a genetic connection with the X chromosome. The frequency of dyschromatopsia in the Caucasian American male population is about 7%. However, it is thought that this proportion might be smaller among males of other ethnicities. We want to estimate the proportion of Asian American males who are color-blind. How large a sample size do we need in order to obtain a 95% confidence interval with a margin of error no greater than 5%, or 0.05? Use 0.5 for p̂.arrow_forward
- please help!arrow_forwardWhat is the difference from a controlled variable and the control in a scientific experiment?arrow_forwardPap smears are a diagnostic test used to detect cervical cancer. Although the test has high specificity, it also has low sensitivity. As a result, women have to be screened often. Using the definitions of sensitivity and specificity, explain why increased frequency of screening is needed when sensitivity is low and specificity is high.arrow_forward
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