A recent study indicated that 18% of people free from cardiovascular disease were considered obese. An investigator hypothesizes that a higher proportion of patients with a history of cardiovascular disease will be considered obese. Including 464 patients in the study would ensure that the power of the test is 80% to detect a 5% difference in the proportion with obesity.   True or False?

Public Agenda conducted a survey of 1379 parents and 1342 students in grades 6-12 regarding the importance of science and mathematics for success in life after school. 50% of the students thought these skills were essential and 62% of the parents thought these subjects were crucial for success. The two random samples were selected independently of each other. Is there enough evidence to conclude that the proportion of parents who feel science and math are important for success is higher than the proportion of students who feel the same way? Conduct your test with a level of significance of 0.05.

A hospital claims that 40% of its patients request a telephone. you are interested in disproving this claim. you select a random sample of 250 patients and find that 85% requested a telephone. what is the test statistic for this test?

What conclusions can be drawn from a study with a “statistical significance” result?   What information do you look at to evaluate whether an effect obtained in an experiment is large enough to have a “practical” or “clinical” significance?

30.5% of cases fall below what z- score?

A large company that produces a "tat-burner pill claims an average Ioss of 20 pounds in the first month. A consumer advocacy group believes that this claim is actually just "hype" intended to sell more of the compound. The advocacy group Would like to obtain statistical evidence about this issue and takes a random sample of 100 consumers who responded that they had purchased the pill but didn't know what the survey was about. They find that these 100 people lost an average of 18 pounds. Let the standard deviation of the population be 7.5 pounds. Clearly state the hypotheses, obtain the test statistic and p-value, and state the decision and conclusion. Show all your work.

It is believed that nearsightedness affects about 8% of all children. In a random sample of 220 children, 26 are nearsighted.(a) Construct hypotheses appropriate for the following question: do these data provide evidence that the 8% value is inaccurate? __Ho: p = .08Ha: p > .08 __Ho: p = .08Ha: p < .08 __Ho: p = .08Ha: p ≠ .08 (b) What proportion of children in this sample are nearsighted? _______ (round to four decimal places)(c) Given that the standard error of the sample proportion is 0.0195 and the point estimate follows a nearly normal distribution, calculate the test statistic. Z = _______ (round to two decimal places)(d) What is the p-value for this hypothesis test? P-value = __________ (round to four decimal places) (e) What is the conclusion of the hypothesis test? Since p ≥ α we do not have enough evidence to reject the null hypothesis Since p<α we reject the null hypothesis and accept the alternative Since p ≥ α we accept the null hypothesis Since p ≥ α we reject…

You read an online article that claims that 62% of 8-year-olds have social media accounts. You want to investigate that specific claim, so you set up a one-way chi square analysis and recruit 130 8-year-old participants for your sample. What is the expected frequency for the number of 8-year-olds in your sample who have social media accounts? mard Next

A union of restaurant and foodservice workers would like to estimate the mean hourly wage, u, of foodservice workers in the U.S. this year The mean hourly wage last year was $8.16, and there is good reason to believe that this year's value is greater than last year's. The union decides to do a statistical test to see if the value has indeed increased. The union chooses a random sample of this year's wages, computes the mean of the sample to be $8.43, and computes the standard deviation of the sample to be $1.25. Based on this information, complete the parts below. (a) What are the null hypothesis H, and the alternative hypothesis H, that should be used for the test? H, :0 OSO H :0 D=0 (b) Suppose that the union decides not to reject the null hypothesis. What sort of error might it be making? (Choose one) (c) Suppose the true mean hourly wage for foodservice workers in the U.S. this year is $8.16. Fill in the blanks to describe a Type I error. A Type I error would be the hypothesis that…

A software company is interested in improving customer satisfaction rate from the 65% currently claimed. The company sponsored a survey of 248 customers and found that 170 customers were satisfied. What is the test statistic z?