Recall from Chapter 1 (see page 34) 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.
Open the Focus sample worksheet (FocusSample) in the technology of your choice and do the following.
a. Find the linear correlation coefficient between cumulative GPA and high school percentile for the 200UWECundergraduate students in the Focus sample.
b. Repeat part (a) for cumulative GPA and each of ACT English score, ACT math score, and ACT composite score.
c. Among the variables high school percentile, ACT English score, ACT math score, and ACT composite score, identify the one that appears to be the best predictor of cumulative GPA. Explain your reasoning.
Now perform a regression analysis on cumulative GPA, using the predictor variable identified in part (c), as follows.
d. Obtain and interpret a scatterplot.
e. Find and interpret the regression equation.
f. Find and interpret the coefficient of determination.
g. Determine and interpret the three sums of squares SSR, SSE, and SST.