An increase in MPK
r
or decrease in PK/P
§ increases the
profnvestment at any r1 given interest rate
§ shifts I curve to
the right.
CHAPTER 18 Investment
CHAPTER 18 Investment
8
The cost of capital
Components of the cost of capital:
interest cost: i PK, where PK = nominal price of capital
depreciation cost: PK, where = rate of depreciation
§ why investment rises during booms and falls
during recessions
Three types of investment
§ Business fixed investment:
businesses’ spending on equipment and structures for use in production.
For the Cobb-Douglas production function,
the MPK (and hence equilibrium R/P ) is
Y A K L1
R MPK A L K 1
P
The equilibrium R/P would increase if:
Then,
$1000