1. An educational psychologist wants to see if students' ID GPA Hours
grade point averages are related to how many hours per
17 3.12 10.5
week they spend studying. To that end, the psychologist
24 4.00 18.0
takes a random sample of students at UWL and records
61 2.85 7.5
for each student in the sample the GPA and average
63 2.51 3.5
number of Hours per week spent studying (as reported
65 2.16 9.0
by the student). The data is displayed at right. Renam-
82 3.62
20.0
ing GPA as y and Hours as x, the five basic statistics
84 3.54 12.0
are T = 11.5, y = 3.11, SSxx = 202.0, SSyy = 2.57, and
SSxy = 18.5.
(a) Find the regression line, using GPA as the dependent variable, and Hours as the
independent variable.
(b) Find the correlation coefficient of GPA with Hours.
(c) Give a test statistic and P-value for a test of the claim that there is a relationship
between the two variables.
(d) What is the predicted GPA for a student who averages zero hours per week studying?