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 Is the amount of sleep that Americans get more than 8 hours per day? In 2013, the Bureau of Labor Statistics, conducted a survey. They asked the participants to make a diary of what they did during a 24 hour period. The sample size was 104. The sample mean amount of sleep was 8.74 hours and the sample standard deviation was 2.4. What is the test statistic?

Do less men(m) then women(f) enroll in engineering courses? What would be the correct alternative hypothesis?

Is there a difference in the population mean time spent watching tv per day for men and women? The p-value was 0.11. What can be said about the 90% confidence interval for the population mean difference?

Is the mean nursing salary for men and women with similar experience statistically significantly different? A significance test was conducted to test this claim. The p-value was 0.07. What can be said about the 90% confidence interval for the population mean difference?

A nutritionist was interested in determining if participating in a weight loss program could reduce someone’s cholesterol levels. She had 4 participants participate in a medical diet plan. She recorded their cholesterol level at the beginning of the program and at the end of the program. Find the 95% confidence interval for the population mean change in cholesterol level. 1 2 3 4 before 220 250 210 220 after 210 225 210 240  

A press organization was interested in studying people’s voting habits. One hundred randomly selected registered voters over the age of 50 and one hundred randomly selected voters between the ages of 30 and 50 were asked if they had decided who they were going to vote for in the presidential election.  Would this be an example of independent or dependent samples?

A political scientist is interested in studying how Americans feel about having a female American president. He asks 100 liberals and 100 conservatives if they would vote for a women president. The political scientist hypothesized that more liberals(1) would vote for a women president than conservatives(2). What would be the correct null and alternative hypothesis?

Researchers were trying to determine if a connection could be made between television viewing habits and gender. They want to see whether less men (m) watch the television show, Game of Thrones, than women (f). What would be the correct alternative hypothesis?

A press organization was interested in studying people’s voting habits. One hundred randomly selected registered male voters and one hundred randomly selected female voters were asked if they had decided who they were going to vote for in the presidential election.  Would this be an example of independent or dependent samples?

A fellow student says that the average salary of graduates in your major is 30,000 dollars per year. You don’t think that this is correct. You think that the average salary is different from this. To show that your fellow student is wrong, you take a simple random sample of fifty graduates who have graduated in the past 5 years and ask for the amount of their starting salary. We want to investigate whether there is evidence to support your claim that the population mean starting salary is different from 30,000 and find that the p-value is 0.005.    What can be said about the 99% confidence interval for the population mean difference?