production is
converting inputs into outputs
firms must make ---- to earn profit
products (output)
inputs are the ---- used to make outputs
resources
input resources are also called
factors
total physical product is
the total output or quantity produced
marginal product is
the additional output generated by additional inputs (workers)
marginal product formula
change in total product divided by change in input
average product
total product divided by units of labor
fixed resources
resources that don’t change with the quantity produced
variable resources
resources that do change with the quantity produced
law of diminishing marginal returns
as variable resources are added to fixed resources, the additional output produced per additional worker will decrease
three stages of return
increasing marginal returns
decreasing marginal returns
negative marginal returns
increasing marginal returns
marginal product is rising and total product is increasing at an increasing rate due to specialization
decreasing marginal returns
marginal product is falling and total product is increasing at a decreasing rate because of fixed resources (each worker adds less and less)
negative marginal returns
marginal product is negative and total product is decreasing because workers get in each others way
short run
at least one resource is fixed, production capacity is fixed
long run
all resources are variable, no fixed resources, production capacity is changeable
total costs
total fixed cost, total variable cost, total cost
per unit costs
average fixed costs, average variable costs, average total costs, marginal cost
fixed cost
cost for fixed resources that don’t change with the amount produced
average fixed cost (AFC) formula
fixed cost divided by quantity
variable cost
cost for variable resources that do change as more or less is produced
average variable cost (AVC) formula
variable cost divided by quantity
total cost
sum of fixed and variable costs
average total cost formula
total costs divided by quantity
marginal cost
additional cost of an additional output
marginal cost formula
change in total costs divided by change in quantity
ATC and AVC curves will
get closer but never touch
marginal product curve reasoning
more workers are hired → marginal product increases → law of diminishing marginal returns → marginal product decreases
MP and MC are mirror images
marginal cost curve reasoning
marginal cost of units produced decreases as marginal product increases, eventually increases due to diminishing marginal returns
MP and MC are mirror images
ATC shape reasoning
when MC is below average, it pulls ATC down and when MC is above average, it pulls ATC up, and this creates bowl curve
MC intersects the ATC at
the ATC’s lowest point
returns to scale
increasing
constant
decreasing
increasing returns to scale
when doubling input, output more than doubles
constant returns to scale
when doubling input, output doubles
decreasing returns to scale
when doubling input, output less than doubles
long run ATC curve is made up of
all the different short run ATC curves
why do economies of scale occur
firms that produce more can better use mass production techniques and specialization
LRATC - economies of scale
mass production techniques are used so LRATC falls
LRATC - constant returns to scale
LRATC is as low as it can get
LRATC - diseconomies of scale
LRATC increases as firm gets too big and difficult to manage
LRATC graph
downward slope → economies
constant slope → constant
upward slope → diseconomies
diminishing marginal returns don’t apply in the long run because
there are no fixed resources
total revenue formula
price x quantity
profit formula
total revenue - total cost
explicit costs
payments made by firms for using the resources of others, AKA out of pocket costs
implicit costs
opportunity costs that firms pay for using their own resources
accounting profit
total revenue - accounting costs
economic profit
total revenue - economic costs
profit maximizing rule
MR = MC
shut down rule
firms should continue to produce as long as price is above AVC
if price is below AVC, minimize loss by shutting down bc loss is bigger than fixed coss
shut down if P < AVC
marginal cost and supply
price increases → quantity increases
price decreases → quantity decreases
MC increase → supply decrease
MC decrease → supply increase
MC above AVC is a ---- supply cirve
short run
barriers to entry
factors that prevent new firms from entering a given market
low barriers → more competition → less profit per firm
high barriers → less competition → more profit per firm
normal profit
no economic profit
in an efficient competitive market, firms with identical products make a normal profit
four market structures
perfect competition
monopolistic competition
oligopoly
monopoly
imperfect competition markets
monopolistic competition
oligopoly
monopoly
perfect competition characteristics
many small firms
identical products (perfect substitutes)
low barriers
seller has no need to advertise
price takers → no control over price
types of barriers to entry
economies of scale
only one electric company because they can make electricity at lowest cost
natural monopoly
superior technology
geography/ownership of raw materials
government created barriers
patents
monopoly characteristics
one large firm
unique product (no close substitutes)
high barriers
monopolies are price makers
oligopoly characteristics
a few (less than 10) large producers
identical or differentiated products
high barriers to entry
price maker
mutual interdependence
firms worry about decisions of competitors and use strategy
monopolistic competition characteristics
relatively large number of sellers
differentiated products
some control over prices
low barriers
non-price competition (advertising)
why perfectly competitive firms are price takers
charge above market price → nobody will buy
charge below market price → not necessary because demand stays the same
price is the same at all quantities demanded
demand curve is perfectly elastic
price taker means
price is set by the industry
for perfect competition, MR =
MR = D = AR = P
for perfect competition, the demand curve is
industry → downward sloping line
firm → horizontal line
perfect competition firm profit
MC = MR intersection down to ATC
characteristics of MR = MC
applies to all markets
only applies of P > AVC
can be restated as P = MC for perfectly competitive firms
per unit tax is an example of a ---- increase
variable cost
causes supply to decrease
subsidy is an example of a ---- decrease
variable cost
causes supply to increase
if fixed cost increase, quantity will
remain the same because MC/supply doesn’t change
per unit tax ---- affect the quantity produced
will
lump sum tax ---- affect the quantity produced
will not
change in fixed cost changes
ATC and AFC but not MC
change in variable cost changes
ATC, AVC, and MC
perfect competition in the long run
profit → firms enter
loss → firms leave
all firms break even (make no economic profit)
no economic profit = normal profit
extremely efficient
no economic profit is the same as ---- accounting profit
positive
change in number of firms impacts market supply by
firms leave → price increases → quantity decreases
constant cost industry
entry of new firms into the market does not increase the costs for firms already in the market
in a constant cost industry, supply curve is
horizontal
in an increasing cost industry, the supply curve is
upward sloping
productively efficiency
producing at the lowest possible cost (P = min ATC)
allocative efficiency
producing at the amount most desired by society (P = MC)
long run perfectly competitive firm efficiency
allocative and productive
short run perfectly competitive firm efficiency
allocative but not productive