AECO410/510 : Suggested Answers to PS 1
Fall 2012
1. Suppose that n is an odd number. Then by the denition of odd number,
n = 2k + 1 for some integer k: Hence
n2
=
=
=
=
(2k + 1)2
4k 2 + 4k + 1
2(2k 2 + 2k ) + 1
2k + 1
where k = 2k 2 + 2k is also an integ
1. (a) For each of the following cases, write down the appropriate estimation strategy such as OLS,
2SLS, WLS, Probit, Logit, Tobit, Heckit, or Poession regression
1. We would like investigate the determinants of charitable giving. For 1500 individuals, w
Eco 420Z. Applied Econometrics
Midterm 1. Oct. 14. 2008
Name and ID No.
Instructions: There are 4 questions and 60 points. Point allotments are indicated in parentheses. DO
NOT FORGET TO WRITE DOWN YOUR NAME AND ID. NUMBER! Good luck!
1. Circle the approp
Eco 420Z. Applied Econometrics
Homework 2
Problems:
1. Solve question 4.2 in page 159 of your textbook.
2. Solve question 4.5 in page 160 of your textbook.
3. Solve question 6.3 in page 216 of your textbook.
Computer Exercises:
Please submit a log file pr
Eco 420Z. Applied Econometrics
Homework 1
1. Regression analysis with cross-sectional data
a) Solve question 3.1 in pp.105-106 of your textbook. Comment on the
estimated R2 .
b) Solve question 3.9 in p. 108 of your textbook.
c) Solve question 3.12 in p. 1
AECO410/510 : Midterm Practice Questions
Fall 2012
1. Using proof by contradiction method to show that if a,b 2 Z (the set of
integers),then a2 4b 6= 2.
2. Use both mathematical induction to prove that
n
P
j 3 = n2 (n + 1)2 =4.
j =1
3. Write down the line
AECO410/510 : Problem Set 5
Fall 2012
Due on Nov 09, 2012
1. Determine whether f (x) = jxj is convex or concave.Please justify your
answer.
1
2. Find the extreme points of f (x) = x + x for x 2 (0; 1): Is it a maximum,
minimum or saddle point. Is the func
AECO410/510 : Problem Set 4
Fall 2012
Due on Oct 15, 2012
1. Find f 0 (x) via the method of inverse function for f (x) = cos
jxj 1.
1
x where
2. Find quadratic approximation to y = y (x) about x = 0 for y when y is
dened implicitly as a function of x by t
AECO410/510 : Problem Set 3
Fall 2012
Due on Oct 05, 2012
1. Determine whether the function f (x) = 2(x + 5)3 + 1 is one to one. Is it
also onto? Please justify your answer.
2. .
(a) Find lim
x!0
0
p
x+4 2
.
x
(b) Find f (5) for f (x) = jx
5j if it exists
AECO410/510 : Problem Set 1
Fall 2012
Due on Sep 21, 2012
1. Write down the linear function y = f (x) that pass through points (0; 1)
and (1; 0) ; What are the slope and intercept of the linear function?
2. Suppose the market demand and supply functions a
AECO410/510 : Problem Set 1
Fall 2012
Due on Sep 07, 2012
1. Using proof by contradiction method to show that if n2 is an even number,
then n is also an even number.
2. Let an = n(n1 : Compute a1 ; a1 + a2 ; a1 + a2 + a3 ; a1 + a2 + a3 + a4 . Then
+1)
gue
AECO410/510 : Answers to Problem Set 4
Fall 2012
1. The inverse function of f (x) is g (x) = cos(x):Hence g (f (x) = cos(cos 1 x),
from which we get g 0 (f (x) = sin(cos 1 x) because g 0 (x) = sin(x).
p
1
Then f 0 (x) = g0 (f1(x) = sin(cos 1 x) . Note tha
AECO410/510 : Answers to Problem Set 3
Fall 2012
1. The function f (x) = 2(x + 5)3 + 1 is one to one for x 2 R. To see this,
suppose f (x1 ) = f (x2 ) for x1 , x2 in R. Then we have 2(x1 + 5)3 + 1 =
2(x2 + 5)3 + 1. Hence (x1 + 5)3 = (x2 + 5)3 , from which
AECO410/510 : Answers to Problem Set 2
Fall 2012
Due on Sep 21, 2012
1. Note that (x1 ; y1 ) = (0; 1) and (x2 ; y2 ) = (1; 0)
y = ax + b
where
a=
0
y1
=
x1
1
y2
x2
1
=
0
1:
and
b = y2
ax2 = 0
( 1)1 = 1
hence
y=
Thus the slope is
puted as
x+1
1 and the int
Midterm Examination
Question 2
Economics 466Y
Bruce C. Dieffenbach
March 8, 2012
Consider a stock for which each period the dividend Dt rises by 10%, so
the expected future dividend is
Total time: 80 minutes.
The market interest rate R = .20 is constant.