16.5/20
Problem Set #1
Summer 2016
Mingsheng Xu
1a. supp(X)=cfw_1,2,3.,N ,N is any given integer
1b. P(X=1)=1/6
1c. P(X=2)=5/36
if n =.
1d. P(X=n)=(5/6)(1/6)
1e. Firstly, P(X=n)>0, n supp(X)
Secondly, P(X=1)+ P(X=2)+.+ P(X=n)= 1/6+5/36+(5/6)(1/6)=1
7.5/8
Income Growth and Implications:
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See this website for understanding and exploring
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1
Y A * K (hL)
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y Ah
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Department of Economics
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Matrices
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Transpose
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x1
x2
x = . .
.
.
xn
Then the expectation of x, denoted
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Department of Economics
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Matrix-scalar multiplication
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Department of Economics
Purdue University
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I
Matrix multiplication is associative. That is, when defined,
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Problem Set #4
Econ 572
(1) First, lets expand the traditional formula. Note that
X
X
X
X
1 X
(xi x)(yi y) =
xi )(
yi ).
xi yi nxy =
xi y i (
n
i
i
i
i
i
Likewise, for the denominator:
X
(xi x)2 =
X
i
x2i nx2 =
i
X
i
x2i
1
n
!2
X
xi
.
i
Multiplying each
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Questions 1-4 are worth 10 points each; questions 5-7 are worth 20 points each.
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18
MS-Econ 590
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Questions 1-3 and 6 are worth 15 points, question 4-5, 7-8 is 10 points.
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MS-Econ 590
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Each question is worth 25 points.
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.
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Soft
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