Answer Any 5 of the Following a Through F:
A) $\mathrm { GPA } _ { \mathrm { i } } = 3.1 + 0.02 \mathrm { ST } _ { \mathrm { i } } + \mathrm { e } _ { \mathrm { i } }$

Essay

Answer any 5 of the following A through F:
A) Briefly explain in words how diplomatic parking fines can be used to predict the level of corruption in a nation. Also, write the econometric model used to make this prediction.
B) Define psychometrics.
C) Explain why minimizing the squared error terms is the premier method for fitting a line between observations considering that other options are available.
D) Give 3 distinct reasons why a student may not reduce their study time given the information in the box on the right. $\mathrm { GPA } _ { \mathrm { i } } = 3.1 + 0.02 \mathrm { ST } _ { \mathrm { i } } + \mathrm { e } _ { \mathrm { i } }$
(0.14) (0.08) $\leftarrow$ standard errors
where GPA is grade point average
ST is hours of study time on a typical day.
$$\mathrm { r } ^ { 2 } = 0.0002 \quad \mathrm { n } = 289$$
E) Prove
$\Sigma \left( X _ { i } - \bar { X } \right) ^ { 2 } = \Sigma X _ { i } { } ^ { 2 } - n \bar { X } ^ { 2 }$ F.
F. Prove
$\Sigma \left( Y _ { i } - \bar { Y } \right) = 0$