Econ 371 Problem Set #1 Answer Sheet 2.1 In this question, you are asked to consider the random variable Y , which denotes the number of "heads" that occur when two coins are tossed. a. The first part
Econ 523, Spring 2007
Prof. Tom Hertz
Study Guide for Exam 2, part 2 (Chapters 12 & 13)
Chapter 12
In section 12.1 and 12.2, read up to page 428, including Eq. 12.4. That equation is what I
write as C
Econ 523, Spring 2007
Prof. Tom Hertz
Study Guide for Exam 2 (Part 1: Chapters 6-9)
The exam covers chapters 6,7,8, 9, 12, and 13. Recall, however, that not all sections are
required. I dont think tha
Econ 783, Spring 2007
Tom Hertz
What Makes a Good IV Regression?
1) A vigorous defense of the validity of the instruments, on a priori grounds (i.e. based
on reasoning, not your results). Recall that
Econ 522, Fall 2006
Prof. Tom Hertz
Study Guide for Exam 2
The exam covers chapters 8, 9, 10, 12, 13, and 14. Recall, however, that not all sections are
required. I dont think that re-reading each cha
Econ 523, Spring 2007
Prof. Tom Hertz
Note on Degrees of Freedom Adjustments and Samples versus Populations
N? N-1? N-2? N-K-1?
Although it is true that in large datasets (like our sample of 935 worke
Econ 523, Fall 2007
Tom Hertz
Notes on Measurement Error
The key point here is that when we have noisy x-variables, i.e. variables that are measured
with some error, the regression coefficients associ
Econ 522, Spring 2007
Tom Hertz
Handout on Omitted Variables Bias
Suppose the true model is:
y 0 1 X 1 2 X 2 u
But we omit X2 in our regression, and generate estimates using only X1:
y 0 1 X 1
If we h
Econ 522, Fall 2006
Prof. Hertz
Notes on Creating Interaction Terms
We saw that creating interactions between variables can sometimes lead to strange estimates of
the direct effect of either or both v
Discussion Section 4
ECON 139/239
2010 Summer Term II
1. Lets use the CollegeDistance.csv data again.
(a) An education advocacy group argues that, on average, a persons educational attainment would in
r , Spring 2007 Name: E 2
iiertz
First Exam
PART ONE: Circle letter of your choice; read all options before deciding (I point each)
1. The probability density function for a discrete random variable X