ECON 2020 Flashcards
UTILITY
the satisfaction a consumer obtains from the
consumption of a good or service
Utility is measured in
utils
TOTAL UTILITY
the total satisfaction a person derives
from consuming some specific quantity; TU and Qd move TOGETHER; TU = Σ MU
MARGINAL UTILITY
the additional utility a consumer
derives from an additional unit of a good
LAW of DIMINISHING MARGINAL UTILITY
MU and Qd move OPPOSITE
Marginal Utility=
ΔTU / ΔQ
NOTE: As MU falls, willingness to pay falls as well
BUDGET LINE/CONSTRAINT
line that shows the different consumption bundles a consumer can purchase with a specific money income
CONSUMPTION BUNDLE
the combination of goods and services
consumed by an individual
NOTE: the price of a consumption bundle cannot exceed the consumer’s total income
INCOME=
(Qx * Px) + (Qy * Py)
OPP. COST of X =
max Qy / max Qx = Px / Py
FACTORS THAT CHANGE THE BUDGET LINE
- Income- decrease or increase in available funds.
- Price of Y- A change in price causes a rotation of the budget line
- Price of X- A change in price causes a rotation of the budget line
MARGINAL UTILITY PER DOLLAR=
MU/P
If we buy stuff to maximize total utility,maximize total utility, and we stop buying stuff when all income is spent, then…
What Do We Buy First?
The good that gives us the most (marginal utility)
For utility maximization, the consumer must get the same amount of utility from the last dollar spent on each good.
In other words, consumers reach the optimal consumption bundle when:
- All income is spentAll income is spent
- MUx / Px = MUy / Py
OPTIMAL CONSUMPTION BUNDLE
the bundle that maximizes total utility
If prices change, we either have to…
rewrite the table or use a graph
INDIFFERENCE CURVE
a line that shows the consumption bundles
that yield the same amount of total utility
Properties of (Most) Indifference Curves
- ICs are downward sloping
- ICs farther from the origin represent a greater level of TU
- ICs never cross
- ICs are bowed inward
Slope =
ΔQy / ΔQx
MARGINAL RATE OF SUBSTITUTION
the ratio of the marginal utility of one good to the marginal utility of another;
MRS =
MUx/MUy
PRINCIPLE OF DIMINISHING MRS
- the more of good X a person consumes in proportion to good Y, the less Y the consumer is willing to substitute for X; MRS decreases as Qx increases
- the MRS changes along an IC because of diminishing
marginal utility
RELATIVE PRICE
The ratio of the price of one good to the price of the
other
RP=
Px / Py
NOTE: slope of budget line = - Px / Py
Thus, we can find the optimal bundle by setting
MRS =
RP or MUx/MUy = Px/Py
RELATIVE PRICE RULE
At the optimal consumption bundle, MRS = RP
PERFECT SUBSTITUTES
goods for which the marginal rate of substitution is constant, no matter how much of each is consumed
PERFECT COMPLEMENTS
goods that a consumer will consume in the same ratio regardless of their relative price
PROFIT (Π)=
Π = Total Revenue – Total Cost= Total Revenue – Total Cost
TR =
P * Q
TC can be defined multiple ways:
- Accounting Π = TR – Explicit cost
- Economic Π = TR – Economic cost