Economics 100B
Abhijit Sen Gupta
UCSC
Summer 2006
Answer Key to Problem Set 4
1)
Problem 3,
Chapter 16 of Blanchard
Applying equation (16.5) p. 346:
a.
18000/.05+.08 = 138,462 > 100,000 so buy
b.
18000/.10+.08 = 100,000 so indifferent
c.
18000/.15+.08 = 78,261 < 100,000 so do not buy
2)
Problem 4,
Chapter 16 of Blanchard
a.
Expected Net Present Value of noschool option:
[1.40][40,000
+
40,000/(1+r
t
)
+
40,000/((1+r
t
)(1+r
e
t+1
))
+
40,000/((1+r
t
)(1+r
e
t+1
)(1+r
e
t+2
))…]
for 38 years.
However, as the real interest rate is expected to be zero always this simply becomes
[1.4][40,000]38 = 912,000
 Expected Net Present Value of schoolthenwork option:
[1.40][1.10][40,000/((1+r
t
)(1+r
e
t+1
)) + ….40,000/((1+r
t
)(1+r
e
t+1
)(1+r
e
t+2
)) + .
....]
for 36 years.
Again using that the expected real interest rate is always zero this simply
becomes
[1.40][1.10][40,000]36 = 950,400
 So willing to pay up to 950,400  912,000 = 38,400 to go to school
b. Tax rate of .3 implies willing to pay 1,108,800 1,064,000 = 44,800 to go to school.
3)
Problem 3,
Chapter 17 of Blanchard
a)
A decrease in expected future real interest rate will increase the present discount
value of future earnings. This will increase current consumption and investment
and shift the IS curve to the right.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full DocumentEconomics 100B
Abhijit Sen Gupta
UCSC
Summer 2006
b)
An increase in current money supply will lower current interest rate and increase
current output. This will cause the LM curve to shift right.
c)
Within the context of ISLM, with a fixed capital stock, an increase in expected
future taxes causes IS to shift left.
However, the increase in future taxes (a
deficit reduction program) will lead to lower real interest rates and increased
investment in the medium run and higher output in the long run.
The expected
changes in the real interest rate and output tend to cause the IS curve to shift
right.
The net effect on the IS curve is ambiguous.
d)
A decrease in expected future income will lead to a reduction in current
consumption and investment and shift the IS curve to the left.
4)
Problem 5,
Chapter 17 of Blanchard
These answers ignore any effect on capital accumulation and output in the long run.
a.
In the future, tax cuts will lead to a boom.
This leads to higher expected
output, lower expected taxes, but a higher expected interest rate in the
future. The effect on current output is ambiguous.
b.
This means that the Fed will increase the interest rate in the future (shift
LM left).
The expected interest rate will increase more, but there is still
the effect of lower expected taxes on current consumption.
The effect
today on output is still ambiguous, but more likely to be negative than in
part (a).
c.
Future output will be higher, the future interest rate will not increase, and
future taxes will be lower.
The current IS curve definitely shifts right, and
current output increases.
This is the end of the preview.
Sign up
to
access the rest of the document.
 Summer '07
 YiSun
 Economics, Exchange Rate, International Trade, United States dollar, Abhijit Sen Gupta, Sen Gupta Summer

Click to edit the document details