a. Open the Focus sample (FocusSample) in the statistical software package of your choice and then obtain and interpret a 95% confidence interval for the mean high school percentile of all UWEC undergraduate students. Interpret your result.
b. In practice, the (population) mean of the variable under consideration is unknown. However, in this case, we actually do have the population data, namely, in the Focus database (Focus). If your statistical software package will accommodate the entire Focus database, open that worksheet and then obtain the mean high school percentile of all UWEC undergraduate students.
c. Does your confidence interval in part (a) contain the population mean found in part (b)?Would it necessarily have to? Explain your answers.
d. Repeat parts (a)-(c) for the variables cumulative GPA, age, total earned credits, ACT English score, ACT math score, and ACT composite score.
Recall from Chapter 1 (refer to page 30) that the Focus database and Focus sample contain information on the undergraduate students at the University of Wisconsin - Eau Claire (UWEC). Now would be a good time for you to review the discussion about these data sets.