Explicit Costs
out-of-pocket costs; payments made by firms for using resources (ex: rent, supplies..)
Implicit Costs
the opportunity costs that firms “pay” for using their own resources (ex: inheiritance…)
Accounting Profit
only looks at explicit costs (ACP = total revenue - explicit costs - depreciation)
Economic Profit
looks at both implicit and explicit costs (ECP = total revenue - economic costs (implicit+explict))
Positive Economic Profit
signals best use of resources
Negative Economic Profit
indicates better alternative use of resources
Normal Profit
breaking even (ACP = ECP)
Marginal Revenue
the additional revenue generated from selling one more unit of a good or service. (% change in TR / Q)
Optimal Output Rule
MR = MC
Marginal Cost Curve
The line that shows how the cost of producing one more unit depends on the quantity already produced.
Marginal Revenue Curve
MR = P (stays the same because we assume the market is constant)
Long Run
elastic (can expand/downsize); all costs are varied
Short Run
inelastic (can’t expand or downsize); at least one fixed cost
The Total Production Curve
Shows the relationship between the quantity of output produced and the quantity of the variable input used -all other inputs constant; three stages.
Marginal Product (of labor)
change in Q/change in labor
Diminishing Returns (to an input)
The Q of the variable input is increasing; fixed input stays the same
Fixed Cost
a cost that doesn’t change (ex: rent)
Fixed Input
Production factors that cannot be changed in the short run (ex: land)
Variable Input
Production factors that can be changed in the short run (ex: labor)
Total Cost Curve
Shows the total cost of producing different output levels in the short run.
Average Total Cost
Fixed cost per unit of output; the total fixed price / Q produced.
Spreading Out Effect
As the Q of output increases, fixed costs are spread out over a more significant number of units, leading to a decrease in AFC.
U-Shaped Average Total Cost Curve
Shows how the average total cost changes as the quantity of output produced varies
Average Fixed Costs
Average Variable Costs
Variable cost per unit of output; total variable cost / Q of output produced.
Minimum-Cost Output
The point where the ATC curve is at its lowest; the production level at which the firm produces most efficiently in terms of cost
Long-Run Average Total Cost Curve
Shows the lowest possible ATC of producing different output levels; The law of diminishing marginal returns doesn’t apply in the long run because there are no FIXED RESOURCES.
Increasing Returns (to scale)
When a firm increases its inputs; ATC decreases as the production scale expands. (bread more than doubles)
Economies of Scale
LRATC is falling as the firm expands.
Decreasing Returns (to scale)
When a firm increases its inputs; not benefiting from expansion (bread less than doubles)
Diseconomies (of scale)
LRATC is rising as the firm expands.
Constant Returns (to scale)
Firm increases its inputs by a particular proportion (bread doubles exactly)
Sunk Cost
Lost cost (losing a concert ticket)
Perfectly Competitive Market
Many small firms compete against each other
Perfectly Competitive Industry
Many small firms producing homogeneous or identical products
Market Share
Percentage of total sales in an industry that a company holds over a specific period.
Standardized Product
Uniform and consistent product; in perfect competition
Variable Cost
cost that rises/falls depending on how much is produced (ex: labor)
Total Cost
Fixed cost + Varible cost
Monopoly
One firm controls all (ex: water)
Barrier to Entry
How hard it is to enter a market. (ex: high start-up costs,
Natural Monopoly
Occurs when a single company can serve an entire market at a lower cost than two or more firms could (ex: water)
Patent
A legal protection the government grants an inventor the exclusive right to make, use, and sell an invention for ~20 years
Commodity
Basic good used in commerce that is interchangeable with other goods of the same type
Free Entry and Exit
Easy to enter and exit market (perf. Comp.)
Oligopoly
Afew firms dominate
Monopolistic Competition
Many firms offering similar but slightly differentiated products.