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. Begin by opening the Focus sample (Focus Sample) in the statistical software package of your choice.
a. Obtain a normal probability plot of the sample data for each of the following variables: high school percentile, cumulative GPA, age, total earned credits, ACT English score, ACT math score, and ACT composite score.
b. Based on your results from part (a), which of the variables considered there appear to be approximately normally distributed?
c. Based on your results from part (a), which of the variables considered there appear to be far from normally distributed? If your statistical software package will accommodate the entire Focus database (Focus), open that worksheet.
d. Obtain a histogram for each of the following variables: high school percentile, cumulative GPA, age, total earned credits, ACT English score, ACT math score, and ACT composite score.
e. In view of the histograms that you obtained in part (d),comment on your answers in parts (b) and (c).