A prominent university conducted a survey on the effect ofpart-time work on student grade point average (GPA). Let xbe the hours worked per week and y the GPA for the year. Asummary of the results is below. What can the university concludewith an ? of 0.05?
n = 21
sigmay = 55
,sigma x = 520
sigmay2 = 171
, aigmax2 = 15288
sigmayx = 1275
, sigma ( y ? ?2) = 24
a) Compute the quantities below.
Bhat0 = , Bhat =
What GPA is predicted when a students works 9 hours a week?
b) Compute the appropriate test statistic(s)for H1: ? < 0.
Critical value = ; Test statistic =
Decision:
---Select---
Reject H0
Fail to reject H0
c) Compute the corresponding effect size(s) andindicate magnitude(s).
If not appropriate, input and/or select "na" below.
Effect size = ;
---Select---
na
trivial effect
small effect
medium effect
large effect
d) Make an interpretation based on theresults.
More hours of part-time work significantly predicts a higherGPA.
More hours of part-time work significantly predicts a lowerGPA.
Part-time work does not significantly predict GPA.
