1. Jamie believes that people who watch the news each night do better on a history test (out of 15 points) than people who do not. To test this theory, Jamie asks 7 people to watch the news for an hour each night before bed for one month, and then administers a history test to these participants (in 2012). Jamie knows that, in the general population, people who do not watch the news each night score 7.5 points, on average, on this history test. The data follows. Do people who watch the news each night do significantly better on the history test than people who do not watch the news Assume normal distributions and a = .05. 2012 2013
10 4
12 5
6 10
11 7
9 6
14 6
10 9
2. In question 1, what is Jamie’s independent variable?
3. In question 1, is Jamie’s independent variable measured on a discrete or continuous scale?
4. In question 1, on what scale of measurement is Jamie’s dependent variable measured?
5. Using the data from question 1, construct a frequency distribution graph to display the 7 history scores Jamie obtained from his sample in 2012. What proportion of people in this group scored under 50% on the test?
6. If the distribution of history scores (for the history test mentioned in question 1) is approximately normal in the general population, what is the probabililty of randomly selecting a group of 7 people whose average score is at least 6, if µ = 7.5 and σ = 2?
7. Using the data from question 1, construct the two-tailed 99% confidence interval for the true population mean test score if everyone watched the news each night.
8. Would you have made the same decision based on your results in question 7 as you did in question 1 (i. e., reject or fail to reject the null)? If so, just answer "yes." If not, explain why the decision can be different even though you are asking the same question.