Economics 2302 T-1 Review for Exam 3
As you know, the third exam covers material presented in
video lessons 9 – 11 and textbook chapters 10 – 12 and 16. As always, I urge you to review the
Telecourse Guide Lesson Objectives, Lesson Focus Points, and Practice Test for
each of the lessons in addition to studying this review.
You
will recall that the second exam covered the market structure called perfect
competition. Perfect competition is a
model market structure that gives the student a foundation for analyzing the
profit maximizing behavior of a firm in an industry that gives “ideal results”
in long run equilibrium. As we learn
about other, real world market structures, we should compare the results from
these to that of perfect competition.
The comparison is in terms of efficient allocation of resources, price,
and economic profit in the long run.
Watch for review items that refer back to perfect competition as you
proceed. You might want to go back to
the lessons and chapters on cost of production and perfect competition before
reviewing the chapters and lessons specifically covered by this exam.
For
this exam you will need to:
- Know the definition of
monopoly.
- Understand why a firm
that faces a downward sloping demand curve is a price setter rather than a
price taker.
- Understand that
monopoly power is the power to restrict output in order to charge a higher
price and make economic profits.
This is only possible if the firm faces a downward sloping demand
curve (demand is not perfectly elastic).
- Understand that when
demand slopes downward, marginal revenue is not equal to price for
quantities greater than 1 unit.
Marginal revenue is below the demand curve for quantities greater
than 1. This happens because when
demand slopes downward, it is showing that a firm must lower prices on all
units in order to sell an additional unit.
- Understand that a
monopoly maximizes profit or minimizes loss by producing the quantity
where marginal revenue equals marginal cost. This is true for all market structures. But in perfect competition, the firm
face a perfectly elastic (horizontal) demand curve, so marginal revenue
was equal to price. So in perfect
competition the firm produced the quantity where MR (and price)=MC. When the monopoly produces where MR=MC,
price is greater than MR and therefore price is greater than MC. Hence we see the monopoly does not
“efficiently allocate resources”.
- Understand the
significance of barriers to entry for monopoly. Know the various kinds of barriers to entry. Understand what a “natural monopoly”
is. Know how Alcoa gained monopoly
power in producing aluminum.
- Study a graph of a
downward sloping demand curve and the marginal revenue curve that is
derived from it alongside a graph of total revenue. Note that total revenue is maximum at
the quantity where marginal revenue is zero. For lower quantities (and higher prices), as the firm lowers
the price to sell more, total revenue increases. What is true about the elasticity of demand when a lower price
results in an increase in total revenue?
Note that for quantities beyond that where marginal revenue is
zero, marginal revenue becomes negative.
So lowering the price now causes total revenue to decrease. What is true about the elasticity of
demand in this region where lowering the price causes TR to drop?
- Study a graph showing a
firms average total cost and marginal cost along with a downward sloping
demand curve and marginal revenue curve.
Be able to find the profit maximizing quantity (where MR=MC). Having found the quantity where MR=MC,
look up to the demand curve to see the price that would be charged to sell
this quantity. Now that you see
the price and quantity, you can multiply these to find total revenue. At the profit maximizing quantity you
found using MR=MC, look at ATC to see cost per unit. This amount multiplied by quantity will
give total cost. Profit then, will
be the difference between TR and TC.
Another way to quickly see the economic profit is to take the
difference between price (per unit) and ATC, which gives profit per unit,
then multiply by quantity to get total economic profit.
- Understand that
monopoly might continue to earn an economic profit in the long run while
in perfect competition economic profits are competed away in the long
run. Compared to perfect
competition, the monopolist’s price will be higher and quantity will be
lower. In perfect competition,
price equals marginal revenue, but in monopoly, price is above marginal
revenue. If an industry that was
in perfect competition suddenly became a monopoly, quantity would be
reduced and price would increase (made possible by monopoly power) so that
profits would increase.
- Be familiar with
approaches to regulating monopoly, especially a natural monopoly. An approach that requires price to
equal marginal cost, as it would in perfect competition, would not work
when marginal cost is below the average total cost curve. Why?
What would this mean in terms of profit or loss. Would it make sense to do this if it
required government subsidy to keep the firm in business?
- Know the definition of
monopolistic competition.
- Be familiar with a
graph showing ATC, MC, demand, and marginal revenue for a firm in
monopolistic competition.
Understand that like monopoly, the demand curve slopes downward, so
MR will be below the demand curve.
Use MR and MC to find the profit maximizing or loss minimizing
level of output. Having found the
quantity where MR=MC, look up to demand to see the price. If price is above ATC, the firm will earn
an economic profit in the short run.
Be able to figure this just like in pure monopoly.
- Understand how, in
monopolistic competition, if firms are making economic profits in the
short run, new firms will enter the industry in the long run. This would reduce existing firms’ share
of demand and therefore reduce their profits. On a graph like the one mentioned in item 12 above, picture
the demand and marginal revenue decreasing until demand is just tangent to
ATC. Note that at this point MR
will equal MC at the quantity where demand is tangent to ATC, so normal
profits (zero economic profit) will be received.
- Understand the
conditions for long run equilibrium in monopolistic competition and how
this is arrived at. Note on the
graph, when long run equilibrium is arrived at, quantity will be to the
left of minimum ATC (because of the slope of the demand curve). This means that there will be excess
capacity in monopolistic competition in the long run. Remember that in perfect competition in
long run equilibrium, firms produced where price and MR equaled ATC at
minimum ATC.
- Be able to compare
monopolistic competition to perfect competition in terms of short run and
long run results.
Remember, regardless of market structure, firms
maximize profits by producing the quantity where MR=MC. In perfect competition, since demand is
perfectly elastic, price = marginal revenue at all quantities. In other market structures like monopoly and
monopolistic competition, where demand is less than perfectly elastic, MR is
below the demand curve and so MR is less than price.
Remember, in long run equilibrium, economic profits
are zero in perfect competition and in monopolistic competition (otherwise
firms would enter which is not equilibrium – equilibrium means no tendency for
change).
Remember that in perfect competition long run
equilibrium is reached at the quantity where ATC is minimum (where MC cuts
through ATC) so the firms produce at the most efficient level of output. Long run equilibrium in monopolistic
competition occurs to the left of minimum ATC so there is excess capacity.
- Understand that we can
criticize monopolistic competition because it does come up to the
efficiency standards of perfect competition, that because of product
differentiation that results in firms having less than perfectly elastic
demand curves, there is some inefficiency, but product differentiation
gives us a wide range of product choices – so the little bit of
inefficiency may be a small price to pay.
- Know the definition of
oligopoly. Understand the
importance of interdependence.
- Understand what a
concentration ratio is and how it helps us find oligopoly when there is a
large number of firms in an industry.
- Understand how the
Herfindahl-Hirschman index is computed and how it is used.
- Understand the tendency
for firms in oligopoly to collude.
- Be familiar with OPEC
as an example of an international cartel.
Understand that in a cartel like OPEC, members agree to restrict
output in order to charge a higher price for their product.
- Know the difference
between tacit and overt collusion to limit competition.
- Be familiar with game
theory. Know what is meant by
“strategic choice”.
- Study the “Prisoners’ Dilemma”. Understand dominant strategy. Given the “pay-offs” of two different
choices for two firms, be able to figure what the likely choice will be.
- Understand why
economists generally agree that a world with advertising is more
competitive than a world without advertising.
- Know what price
discrimination is and a firm can engage in price discrimination if it is a
price setter, can prevent resale by the customers charged the lower price,
and is able to segment the market.
Understand that in price discrimination, a firm charges a higher
price to customers with a less elastic demand for the product and a lower
price to those with a more elastic demand.
- Know the definition of
marginal revenue product.
- Understand the profit
maximizing hiring decision is to hire up to where marginal revenue product
is equal to the marginal factor cost.
This is an example of the marginal decision rule. Given a table showing total product for
each of a number of units of a variable factor, and given the price pf the
product, be able to figure marginal product and marginal revenue product
for each variable factor. Then, if
given the cost of a variable factor, determine the number of the factors
to hire.
- Understand why, in a
perfectly competitive market, the firm’s demand curve for an input is the
downward sloping portion of its marginal revenue product curve.
- Once you understand #29
above, you will understand what kinds of things could cause an increase or
decrease in the demand for a factor.
- Understand how using
more of a substitute factor reduces the demand for a given factor while
using more of a complementary factor would increase the demand for a given
factor. Understand how a change in
the productivity of a factor changes the demand for the factor. What are some things that might lead to
a change in productivity?
- Know why we say that
factor demand is “derived demand”.
What is it derived from? If
there is a change in demand for a finished product or even a change in the
quantity demanded of a finished product, there will be a change in the
demand for the factor that produces the product. Understand how this works.
- Understand the
“backward bending” supply of labor curve.
What does the backward bending portion tell us?
- Understand that perfectly competitive
factor markets and product markets both generate an efficient allocation
of resources.
Remember,
the items on this review are intended to help you prepare for questions on your
third exam. The exam is limited to 50
questions and therefore does not hit on every important thing in the chapters
and video lessons you have studied since the second exam. I urge you to review the textbook end of
chapter problems as well as the Telecourse Guide Lesson Objectives and Focus
Points. This will help you when it
comes time to study for the final exam.