Practice Problems for Test 1 Econ 3200 - Introduction to Econometrics Cornell University
Spring 2010 Prof. Molinari
This practice problems have two parts totaling 100 points. I will maintain the same structure for the Test 1 that I am preparing for your c
Professor Francesca Molinari TAs Simon Kwok and Tae-Hoon Lim
Spring 2010
Introduction to Econometrics
Draft of Suggested Solutions to Problem Set 2
Economics 320
1. Question 2.2 from Wooldridge: In the equation Y = 0 + 1 X + u; subtract get Y 0 = 0 + 1 X
Problem Set 5 Practice for Prelim 2 Due Tuesday 04/13/10 at the beginning of class Econ 3200 - Introduction to Econometrics Cornell University
Spring 2010 Prof. Molinari
The exam will consist of TWO parts totaling 100 points. It will be a CLOSED BOOK exam
ECON 3200 Introduction to Econometrics
Answers for Problem Set 4
Problem 1 (Wooldridge 7.6)
In Section 3.3 – in particular, in the discussion surrounding Table 3.2 – we discussed
how to determine the direction of bias in the OLS estimators when an importa
Professor Francesca Molinari TAs Simon Kwok and Tae-Hoon Lim
Spring 2010
Introduction to Econometrics
Draft of Suggested Solutions to Practice Questions for Test 1
Economics 320
Part 1. a) A sequence of random variables Xn converges to X if
n!1
lim P (jXn
ECON 3200 Introduction to Econometrics
Problem set 1
(due date: February 5, 2009)
Problem 1. (Wooldridge C1.1) Use the data in wage1.xls for this exercise.
1. Find the average education level in the sample What are the lowest and
highest years of educatio
ECON 3200 Introduction to Econometrics
Answers for Problem Set 5
Problem 1 (Wooldridge 8.5)
1. No. For each coefficient, the usual standard errors and the heteroskedasticityrobust ones are practically very similar.
2. The effect is −.029(4) = −.116, so th
ECON 3200 Introduction to Econometrics
Problem set 5
(due date: April 2, 2009)
Problem 1 (Wooldridge 8.5) The variable smokes is a binary variable equal
to one if a person smokes, and zero otherwise. Using the data in smoke.xls
we estimate a linear probab
A Study of Cartel Stability: The Joint Executive Committee, 1880-1886
Author(s): Robert H. Porter
Source: The Bell Journal of Economics, Vol. 14, No. 2 (Autumn, 1983), pp. 301-314
Published by: RAND Corporation
Stable URL: http:/www.jstor.org/stable/30036
Does High Public Debt Consistently Stie Economic
Growth? A Critique of Reinhart and Rogo
Thomas Herndon
Michael Ash
Robert Pollin
April 15, 2013
JEL codes: E60, E62, E65
Abstract
We replicate Reinhart and Rogo (2010a and 2010b) and nd that coding errors,
American Economic Review: Papers & Proceedings 100 (May 2010): 573578
http:/www.aeaweb.org/articles.php?doi=10.1257/aer.100.2.573
Growth in a Time of Debt
By Carmen M. Reinhart and Kenneth S. Rogoff*
In this paper, we exploit a new multi-country
historica
Homework 7
Due: Thursday, May 9
1. Consider the stochastic process
=
1 2
+
= 1 2
2
2
where is i.i.d. with mean 0 and variance 1 for 1.
1.1 Does ( ) depend on ? Does ( )?
1.2 Show that ( 1 ) = 12 and ( 2 ) = 13. What is
( ) for 2?
1.3 Is this process w
Homework 7
Due: Thursday, May 9
1. Consider the stochastic process
=
1 2
+
= 1 2
2
2
where is i.i.d. with mean 0 and variance 1 for 1.
1.1 Does ( ) depend on ? Does ( )?
1.2 Show that ( 1 ) = 12 and ( 2 ) = 13. What is
( ) for 2?
1.3 Is this process w
Homework 5
Due: Thursday, April 11
1.
1.1 Let cfw_ be dummy variables for mutually exclusive and exhaustive
categories. Prove that if one estimates the model
= 0 + 1 + 2 +
b
b
b
one will get 0 = =1 , 1 = =1 =1 , and 2 = =1 =1 , where =1 is
the sample a
Documentation for JEC Data
JEC contains weekly observations on prices and other factors from 1880-1886, for a total of n = 326 weeks. These data were provided by Professor Rob Porter of Northwestern University and were used in his paper "A Study of Cartel
Solution for Problem set 4 Econ 3200
Q1
(i) We need to compute the F statistic for the overall significance of the regression
with n = 142 and k = 4: F = [.0395/(1 .0395)](137/4) 1.41. The 5% critical
value with 4 numerator df and using 137 for the numera
Homework 4
Due: Tuesday, April 2
1. This question is about eciency of markets. Let return be the total
return from holding a rms stock from 1990 to 1994. The ecient markets hypothesis says that these returns should not be systematically related to informa
Homework 5
Due: Thursday, April 11
1.
1.1 Let cfw_ be dummy variables for mutually exclusive and exhaustive
categories. Prove that if one estimates the model
= 0 + 1 + 2 +
b
b
b
one will get 0 = =1 , 1 = =1 =1 , and 2 = =1 =1 , where =1 is
the sample a
Econ 3200: Introduction to Econometrics
Professor Stoye
First Prelim, March 7 , 2013
This exam consists of fteen questions, some of which are grouped to form a
larger question. Each question is worth 5 points.
Good luck!
1. Short Answer Questions.
1.1 If
Econ 3200: Introduction to Econometrics
Professor Stoye
First Prelim, February 23 , 2012
This exam consists of four questions, each of which is worth 25 points.
Good luck!
1. Short Answer Questions (5 points each).
b
1.1 Let 1 be the OLS estimator in a si
Econ 3200: Introduction to Econometrics
Professor Stoye
Second Prelim, April 5
This exam consists of three questions. Points are distributed 20-50-30, with a
more detailed breakdown given below. Good luck!
1. Short Answer Questions (5 points each).
1.1 W
Professor Joerg Stoye
TAs Jun Sung Kim and Jos Mrio Lopes
Spring 2012
Economics 3200
Introduction to Econometrics
Suggested Solutions to Problem Set 1
(please contact us in case you find any typo)
1.
a. Note that X 2 is just anotehr random variable that c
Homework 2: Answer Key
1. In the equation y = 0 + 1 x + u; add and subtract
side to get
y = 0 + + 1 x + (u
):
Call the new error v = (u
new intercept is therefore (
on the right hand
); so that E(v) = E(u
) = E(u)
+
),
but
the
slope
is
still
0
1:
= 0. The
Solution for Problem Set 4 ECON 3200
(Please let us know if you find any typo, so we can correct it)
1.
1.1
Our Null is H 0 : 1 = 2 = 3 = 4 = 0 , which we will test at the 5% level.
We can compute the F statistic as
R2 / q
0.0395 / 4
F=
=
1.4085
2
(1 R )
Introduction to Econometrics
Spring 2012, Professor Stoye
Problem Set 1
Due: Thursday, 02/09/11
1 The following is the most recent poll of its kind posted on pollster.com
as this homework is being written.1
PPP (D) / Daily Kos / SEIU
1/26-29/12; 1,000 reg
Introduction to Econometrics
Spring 2012, Professor Stoye
Problem Set 2
Due: Tuesday, 02/21/12
1 Let = 0 + 1 + and suppose that (|) = () = 6= 0. Show
that this model can be rewritten as a model with the same slope (but dierent
intercept) and the property
Homework 3
Due: Tuesday, March 13
1. The following equation describes the median housing price in a community in terms of amount of pollution (nox for nitrous oxide) and average number
of rooms in houses in the community (rooms):
log = 0 + 1 log + 2 +
1.
4. Write down OLS
1
and plug-in
1 =
=
=
(x1i x
1 )
(x1i x
1 )
(x1i x
1 ) = 0. Also, we know
(x1i x
1 )
x1 = 0. Thus, we have
since
yi = 0 + 1 x1i + 2 x2i + ui .
That is,
P
P
(x1i x
1 )(0 + 1 x1i + 2 x2i + ui )
(x1i x
1 )yi
P
P
=
2
(x1i x
1 )
(x1i x
1 )2
Homework 4
Due: Thursday, April 5
1. This question is about eciency of markets. Let return be the total
return from holding a firms stock from 1990 to 1994. The ecient markets hypothesis says that these returns should not be systematically related to info