Consumption and Investement Flashcards
Consumption of forward-looking consumer depends…
on total wealth
Total wealth contain?
-Financial wealth
-Housing wealth
-Human wealth
Financial wealth
The value of checking and saving accounts, stocks and bonds net of liabilities
Housing wealth
The value of the house owned and other real estate net of the mortgages
Human wealth
Present value of the after-tax labor income over the working life
How expectation of higher output in the future affect consumption today ?
- Expected future output increases
–> Expected futur labor income increase
–> Human wealth increases
–> Consumption increases
–> Expected future dividends increase
–> Nonhuman wealth increases
–> Consumption increases
=Consumption may move even if current income does not change –> depend more on current sales, current real interest and expectation of the future.
Investement depends positively on ?
on the expected present value of future profits (per unit of capital)
–> The higher the expected profits, the higher the expected present value and the higher the level of investment.
= consumption can move even if current income doesn’t change
What determine profit per unit of capital?
- The level of sales
- The existing capital stock
permanent income theory of consumption
The modern theory of consumption
Household budget constraint
C t + ( A t + 1 − A t ) = W t/ Pt x L st + r t A t − T t
Theory of Investement
compare the present value of expected profits with the present value of the cost (example: price of a new maschine)
The expected present value is equal to:
the discounted value of expected profit next year, plus the discounted value of expected profit two years from now (taking into ac- count the depreciation of the machine), and so on.
Present value of the expected, discounted real prots generated by the investment: (formula)
V (Πe ) = Πet+1/(1 + rt) + (1 − δ)Πet+2/ (1+rt)(1+re ) + …
The depreciation rate δ per year quantie
how long the machine will last
Example:
Machines: δ is 4%-15%
Buildings and factories: δ is 2%-4%
If the present value is less than 1 what should do the firm? (investment)
the firm should not buy the machine.
–> If it did, it would be paying more for the machine than it expects to get back in profits later
If the present value exceeds 1. what should do the firm ? (investment)
the company is encouraged to buy the new machine
Investment depends positively on ?
both on the expected present value of future profits and on the current level of profit.
–> The higher the expected profits, the higher the expected present value and the higher the level of investment
–> The higher expected real interest rates, the lower the expected present value, and thus the lower the level of investment
Special case for constant interest rates and prots, equal to their current value:
V(Πet)= Πt / rt + δ
User cost (calculation)
rt + δ
Investment (calculation)
It =I(V(Πet))
In the special case (user cost and investement, calculation)
It = I( Πt/ rt +δ )
Investement definition
is a function of the ratio between the prot per unit of capital and the user cost
What determine profit per unit of capital?
- The level of sales
- The existing capital stock
Profit per unit of capital is what as a function?
is an increasing function of the ratio of sales to the capital stock. For a given capital stock, the higher the sales, the higher the profit per unit of capital. For given sales, the higher the capital stock, the lower the profit per unit of capital.
user cost/ rental cost of capital (definition)
the total cost incurred by a firm for using a capital asset over a specific period (Depreciation, Maintenance Costs, Opportunity Cost, Financing Costs)
Tobin’s Q purpose
constructed a variable corresponding to the value of a unit of capital in place relative to its purchase price and looked at how closely it moved with investment
Relationship between
- Stock market: valuation of an already invested unit of capital
-Purchase price for a new unit of capital