73-363 Econometrics
Fall 2015
HOMEWORK 2: Multivariate regression
SOLUTION 20 point
We continue to use the WAGE1 dataset from HW1.
1 [4 points] Consider the following regression output:
Dependent vari
73-261 Econometrics
Fall 2011
Homework 2: Multivariate regression
SOLUTION - 20 points
1 [3 points] Consider the following regression, which was generated using WAGE2 dataset with wage
being the depen
73-363 Econometrics
Fall 2015
HOMEWORK 1: Simple two-variable regression
SOLUTION - 20 points
1 This exercise will continue using the WAGE1 dataset, derived from the 1976 Current Population
Survey, bu
73-363 Econometrics
Fall 2015
Homework 6: Assumptions and multicollineariy
SOLUTION 20 points
1. (8 points) In this task, you will checking the OLS assumptions 4-6 using WAGE1 dataset from
previous ho
73-363 Econometrics
Fall 2015
Homework 5: Applications
1.(5 points) Consider the following function:
y(x) = 0 + 1 log x
1.a Derive approximate and exact change in y (y) resulting from x decreasing (no
73-363 Econometrics
Fall 2015
Homework 8: Heteroskedasticity
Due Wednesday November 11
1. (6 points) Consider the following model:
consumption = 0 + 1income + 2age +3age2 + u
where E(u| income, age) =
1
73-363 Econometrics
Fall 2015
Homework 7: Endogeneity
Solution
1. (7 points) You have data on worker training and productivity, and are trying to prove that training
increases productivity.
1.a [2 p
73-363 Econometrics
Fall 2015
Homework 3: Inference single equation
SOLUTION 20 points
1. (8 points) You have estimated the Cobb-Douglass production function:
,
ln Y 0 1 ln K 2 ln L
where 0 = ln A. Un
73-363 Econometrics
Fall 2015
Homework 10: Binary models and Panel data
SOLUTION 20 points
1. (10 points) You will need the EZUNEM dataset. Background information is in Example 13.8
(Section 13.5)
1.a
73-363 Econometrics
Fall 2015
Homework 9: Time Series
SOLUTION
We will explore Phillips curve, the (alleged) relationship between inflation and unemployment.
You can find discussion of the model, in E
73-363 Econometrics
Fall 2013
Midterm 1 practice questions ANSWERS
Here is a list of questions that will help you prepare the midterm. There are many more questions
here than there will be on the midt
1 =
PN
i=1 (xi x)(yi y )
PN
2
i=1 (xi x)
=
SSxy
SSxx
SS
XY (X)(Y )
= xy
2
(X 2 ) (X)2
x
P
P 2
(Xi X)2
Ui
= N 2
N 1
=
xy = N xy
2 = SSxx =
P 11 x N 1
1 =
W
P i ( 0 + 1 Xi + U i ) 1
P
Wi1 = 0
W i Xi
Assumptions
A1 Population: true population relationship is linear:
y = 0 + 1 x1 + . + k xk + u
A2 Data are random and independent
A3 No linear dependent/constant variables of x
no perfect collinearity
73-363 Econometrics
Fall 2015
Homework 4: F-test and Prediction
SOLUTION - 20 points
1 (10 points) Let's revisit question 3 from Homework 2. It used the WAGE1 dataset, and tried to
explain wage using
73363 ECONOMETRICS
SOLUTIONS TO HW 1
1. (a) The number of variables and observations can be seen by the Stata command describe.
There are 24 variables and 526 observations.
(b) The fraction of female
73363 Econometrics Homework #1
Out: September 1st In: September 8th
Problem Set #1: Questions 1 and 2 are 25 points each. Question 3 is worth 50 points. Report the
command line of Stata that you use f
73-261 Econometrics
October 12, 2011
Midterm #1
SOLUTION 50 points
1. Tepper School of Business conducted a survey of the MBA class that graduated in 2010, and
found a linear relationship between wage
73-261 Econometrics
Fall 2011
Homework 8: Time Series & Discrete Choice
SOLUTION
1. (3 points) Consider the following AR(1) process:
yt = c + yt-1 + et,
where et is i.i.d. r.v. with zero mean and | <
73-261 Econometrics
Fall 2011
Homework 7: Heteroskedasticity
SOLUTION 20 points
1. (6 points) Exercise 8.2 in Wooldridge (p.294 in the 4th edition), with a different expression for
the conditional var
73-261 Econometrics
Fall 2011
Homework 6: Endogeneity
SOLUTION 20 point
1. (5 points) Exercise 3.10 (p.108 in Wooldridge 4th ed.), parts (i) and (ii)
~
Hint: use the E1 1 1 2 formula that we derived i
73-261 Econometrics
PROBLEM SET 5: Assumptions and Multicollinearity
SOLUTION 20 points
Fall 2011
1. (10 points) In this task, you will checking the OLS assumptions 4-6 using WAGE1 dataset.
and regres
73-261 Econometrics
Fall 2011
Homework 4: Multiple hypotheses and prediction
Solution 20 points
1 (12 points) Let's revisit question 3 from Homework 2, dealing with possible controls for ability in
a
73-261 Econometrics
Fall 2011
Homework 3: Inference: single equation
Solution 20 points
1 [18 points] Consider the regression from Q1 of HW2. You will also need the variance-covariance
matrix that you
73363 ECONOMETRICS
SOLUTIONS TO HOMEWORK 2
b2
b2
1. (a) The test statistic is t = SE(b22) = SE(b2 ) , since 2 = 0, with degrees of freedom
= 60 2 = 58. Given signicance level , for all the two-tailed
73363 ECONOMETRICS
SOLUTIONS TO HW 3
1. (a)
Regression Output: The following Stata output represents regression of S, highest
grade completed, on ASVABC, the ability score, SM, highest grade complete
73363 ECONOMETRICS
SOLUTIONS TO HW 4
1. (a) We write one parameter in terms of the rest in the given restriction. In this case, = 1
yi = a + li + ki + ui
yi = a + (1 )li + ki + ui
(yi li ) = a + (ki
73363 - Econometrics Homework #2
Out: Spetember 8th In: September 15th
Questions are equally weighted.
1) A researcher hypothesizes that years of schooling, EDUC, may be related to the number of
sibli
73-261 Econometrics
November 16, 2011
Midterm #2
SOLUTION - 50 points.
Draft: score allocations will be added later
1. [20 points] In US, government pensions (Social Security) are relatively small, an