10. Supplements for testosterone As men age, their testosterone levels gradually decrease. This may cause a reduction in energy, an increase in fat, and other undesirable changes. Do testosterone supplements reverse some of these effects? A study in the Netherlands assigned 237 men aged 60 to 80 with low or low-normal testosterone levels to either a testosterone supplement or a placebo. Could blinding be used in this experiment? Explain. Why is blinding an important consideration in this experiment?53

Support 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.

“Children whose parents smoke in their presence are more likely to develop asthma than children whose parents do not smoke in their presence.” How many tails should be used when looking up the t test statistic for this study?   Question 6 options:   one tail   two tails   Either one tail or two tails - it doesn't matter   there is not enough information to tell.

We are interested in comparing the proportions of men and women who say earning a large salary is very important to them. You surveyed 200 men and 200 women and recorded their answers to the question as “yes” (earning a large salary is very important) or “no” (earning a large salary is not very important).     Yes No Total Men 150 50 200 Women 110 90 200 Total 260 140 400   Test the association between sex and the importance of earning a large salary using a z-test. Provide the null and alternative hypotheses, test statistic, p-value, and conclude test with 0.01 signifigance.

Does the test result Provide sufficient evidence that light alcohol consumption has a negative impact on the driving performance of a sleep deprived driver. Why or why not

Based on these tables, would you accept or reject the hypothesis that individuals in bad neighborhoods commit more crime?

S K The concerns about the impact of technology on our lives are growing. There have been recent research reports about the negative impact of digital technology usage on stress, work productivity, happiness, and overall well-being. In light of these concems, a polling organization asked technology experts about their opinion on our digital life and found that 28% of the experts believe that in the future our lives will be more harmed than helped by their digital environment. In an effort to confirm these results, a local tech company decides to ask 210 randomly selected customers their opinions about their digital life. Answer parts a through c below. a. What is the probability that 35 or more people from this sample are concerned about the digital environment? The probability is 1. (Round to four decimal places as needed.) b. What is the probability that 45 or more people from this sample are concerned about the digital environment? 0. (Round to four decimal places as needed.) The…

Tourism is extremely important to the economy of Florida. Hotel occupancy is an often-reported measure of visitor volume and visitor activity (Orlando Sentinel). Hotel occupancy data for February in two consecutive years are as follows Current Year Previous Year Осcupied Rooms 1,470 1,458 Total 1,750 1,800 Rooms (a) Formulate the hypothesis test that can be used to determine if there has been an increase in the proportion of rooms occupied over the one-year period. (Let p, population proportion of rooms occupied for current year and P2 = population proportion of rooms occupied for previous year.) Ho: P1-P22 0 H: P1- P2 0 Ho: P1- P2 0 Hai P1 P2 = 0 Ho: P1- P2 = 0 H P1- P2 0 Ho: P1- P2 # 0 Hi P1- P2 = 0 (b) What is the estimated proportion of hotel rooms occupied each year? current previous (c) Calculate the test statistic. (Round your answer to two decimal places.) What is the p-value? (Round your answer to four decimal places.) p-value Using a 0.05 level of significance, what is your…

Researchers have noted a decline in cognitive functioning as people age (Bartus, 1990). However, the results from other research suggest that the antioxidants in foods such as blueberries may reduce and even reverse these age-related declines (Joseph et al., 1999). To examine this phenomenon, suppose that a researcher obtains a sample of n = 16 adults who are between the ages of 65 and 75. The researcher uses a standardized test to measure cognitive performance for each individual. The participants then begin a 2-month program in which they receive daily doses of a blueberry supplement. At the end of the 2-month period, the researcher again measures cognitive performance for each participant. The results show an average increase in performance of MD = 7.4 with SS = 1215. Does this result support the conclusion that the antioxidant supplement has a significant effect on cognitive performance? Use a two-tailed test with α = .05. Show your computations.