550 likes | 706 Views
2. Oligopoly. Oligopoly = Competition between multiple firms (still assuming mass market of buyers)Assume number of firms is fixed No immediate threat of entryBase-case: homogeneous firmsProduction technologies identical (i.e., same cost structure)Products identical (i.e., same demand curve)
E N D
1. 1 Strategic Pricing How to price in a game with competitors
2. 2 Oligopoly Oligopoly = Competition between multiple firms (still assuming mass market of buyers)
Assume number of firms is fixed
No immediate threat of entry
Base-case: homogeneous firms
Production technologies identical (i.e., same cost structure)
Products identical (i.e., same demand curve)
Types of competition
Price competition
Quantity competition
Extensions
Product differentiation
Tacit collusion
3. 3 Class Experiment High or Low Production?
4. 4 The Production Game Players: approximately 76 of you
Choices
Capacity = 2 units
Choose 0, 1 or 2 units
Payoffs
No production costs
Price = 160 – Total Production Quantity
Profit = Price x Quantity
5. 5 Competition in mass markets with homogenous products What happens when firms compete in quantity?
What happens when firms compete in price?
6. 6 Price vs. quantity competition Monopoly
Firm can choose quantity or price
Same answer either way
Oligopoly
Firms can still choose quantity or price
Now, however, this matters
Different models
Different conclusions
The key is capacity
The price-competition model assumes all firms have sufficient capacity to serve the entire market
The quantity-competition model is identical to the price competition model with the addition of capacity constraints
So, the quantity competition model is good for situations in which firms are able to commit to production limitations (e.g., via capacity choices)
We will see that
For the same number of firms, price competition results in lower industry profits
As the number of firms increases, profits under quantity competition converge to those under price competition (i.e., due to the more intense competition)
7. 7 Tough price competition
8. 8 Tough Price Competition CD ROM phonebooks
1986: Nynex charged $10,000 per disk for NY directory
ProCD and Digital Directory Assistance
Workers in China at $3.50 daily wage
Outcome similar to ‘Perfect’ competition
Charge $200 each
Price forced down to marginal cost
9. 9 Same market assumptions as before
10. 10 Competition in prices
Firms post prices simultaneously, afterwards see what they sell
P1 and Q1 denote F1’s price and quantity, respectively
P2 and Q2 denote F2’s price and quantity, respectively
Here, price is the choice variable, quantity is the outcome variable
Goods are perfect substitutes (ex: flour, sugar).
Consumers buy from the firm with lowest price(provided price is less than their WTP)
If firms set different prices, the low-price firm gets 100% share(implicit capacity assumption: both firms can supply entire market)
If firms set identical prices, firms get equal market shares
This is known as the “Bertrand” model of oligopolistic competition
11. 11 Informal analysis Suppose F1 believes that F2 will maintain price
Assume the firms begin with identical prices of $600
At this price, 400 customers buy (note: same as monopoly case)
Firms
Split the market (since prices are equal), 200 units each
Have identical profits of ($600 – $200)200 = $80k(note: split the monopoly profit level)
If F1 lowers the price a little, say to $590, it gets 100% market share
No one buys from F2 (if price stays at $600)
F1 gets Q1 = 1000 – 590 = 410 in sales (from demand equation)
Profits are
(590 – 200)410 = $159,900 for F1
0 for F2
F1 wants to do this (ideally, cut price by 1 cent!)
12. 12 Nash equilibrium? It is not realistic for F1 to believe that F2 will maintain price
What is true for F1 is also true for F2
If F1 cuts price a little, F2 loses everything
Therefore, F2 will also cut price to match, if not exceed, F1’s cut
Each firm’s reaction to a price cut is to cut price – where does it stop?
To solve, use Nash equilibrium: posted prices are stable when neither firm wants to change given competitor’s price
If firms charge different prices, the high priced firm wants to switch to a lower price, so prices must be equal
If common price above marginal cost, both firms prefer to shave price to gain 100% share, so price must be less than or equal to MC
If common price is less than marginal cost, both firms prefer to exit the market and sell nothing at all, so price must equal MC
13. 13 Outcome of pricing game Each firm has a marginal cost of $200
So, both price at $200
Quantity sold is 1000 – 200 = 800 units
Each firm gets 50% share (400 units)
Neither firm makes a profit
This is an insidious outcome, neither firm can raise price without risking entire loss of share
Actually, it’s worse than that …
14. 14 Price trap with no exit Since both firms earn 0 profit, each is indifferent to exiting
But, is it a Nash equilibrium for one to exit
If one firm exits, the other charges the monopoly price ($600 is the best reply of the remaining firm to a competitor that stays out)
But, if one firm stays and charges $600, the other firm wants to enter and charge slightly less
This cannot be a stable situation (Nash equilibrium)
Besides, who would “volunteer” to leave?
It is only Nash for both firms to post P = MC
Otherwise, either someone wants to enter
Or, someone wants to cut price
15. 15 Usual objection
But won’t each firm realise that if it cuts its price the other firm will follow?
(hold that thought…we’ll address soon)
16. 16 Fixed costs, exit and entry Outcome is P = MC
No fixed costs are covered
If firms have no fixed costs, they earn zero profits
If they have fixed costs, they have losses
In the long run, firms w/fixed operating costs must exit
Question is: what happens then?
If entry is free, price competition happens all over again (as discussed on previous slide)
If entry is costly, no entry occurs
The moment an entrant comes in, prices drop to MC
Incumbent earns monopoly profit because the threat to cut price to MC is credible in this situation (i.e., it is a Nash equilibrium)
This is why it may be rational for firms to try to hold out
Need to be careful using this reasoning … if it is rational for you to hold out, it is probably rational for your competitor to do so as well
Amazon.com investors will never get a positive return on their investment
Better: differentiate your product
17. 17 Softer, quantity competition
18. 18 Competition in quantities
Firms simultaneously choose quantities, afterwards see prices
Think of this as choosing capacities
Q1 denotes F1’s quantity
Q2 denotes F2’s quantity
The market-clearing price is P
Here, quantity is the choice variable, market price is the outcome variable
Again, goods are perfect substitutes (ex: flour, sugar).
However, there may not be enough capacity to serve entire market
Since products are identical, prices are identical
Capacity limitations imply higher market-clearing prices than price competition
This is the “Cournot” model of oligopolistic competition
19. 19 Informal analysis Assume the firms begin with identical capacities of 200
To sell all their product (400 units, total), market price is $600 (again, same as monopoly case)
Firms have identical profits of ($600 – $200)200 = $80k(split the monopoly profit level)
Suppose F1 believes that F2 will maintain capacity
What capacity should F1 choose? A partial schedule of outcomes is
20. 20 F1’s “residual” demand curve Preceding table shows F1’s demand when F2 maintains quantity/capacity
It is D1 = 800 – Q1 (just subtract Q2 = 200 from market demand schedule)
21. 21 F1’s reaction curve The preceding analysis can be done for any quantity choice by F2
This results in a schedule of best responses for F1 given any Q2
22. 22 Equation of the reaction curve F1’s MR when F2 chooses Q2 is MR = (1000 – Q2) – 2Q1
So, if MR = MC: (1000 – Q2) – 2Q1 = 200
Rearranging terms: Q1 = 400 – ˝ Q2
23. 23 Nash equilibrium F2 also has a reaction curve, which can be plotted along with F1’s
Nash equilibrium is the point of intersection: both firms best reply
24. 24 Outcome of pricing game Each firm chooses capacity of: 800/3 ? 267
Market price is: 1000 – 1600/3 ? $467
Each firm has profit = (467 – 200)267 = 71,200k
Much better outcome than price competition
Not quite as good as sharing monopoly profit
Firms would prefer to collude and profit more
This is illegal
Even if it weren’t, how would firms prevent cheating?
At quantities of 200, both want to produce more
Check the reaction curves!
25. 25 MR in Monopoly vs. Cournot
26. 26 The 2 components of MR To sell one more unit, you have to
Must sell to someone with lower WTP ? price drops
This drops price to currently buyers
If monopolist is selling 400 and wants to sell 401, she must lower the price on 400 units
Under Cournot, only consider effect on units YOU sell
If firms sell 200 each, lower price effects you only through your existing 200 customers
When making decisions, you don’t care what happens to competitor’s profits
Less downside for you (MR falls slower)
You are more inclined to cut price (have more capacity)
27. 27 Now, the general 2-firm Cournot case Demand: P = a – bQ where a and b are constants and Q = (Q1 + Q2) is the market quantity
Firms have identical, constant marginal costs = C
F1 profit maximized where MR1 = MC1
TR1 = PQ1 = (a – bQ1 – bQ2)Q1 = (a – bQ2)Q1 – bQ12
MR1 = ?TR/?Q1 = (a – bQ2 ) – 2bQ1
Setting MR = MC: (a – bQ2 ) – 2bQ1 = C
Rearranging terms gives reaction function for F1:
Since the firms are symmetric the reaction function for F2 is identical
Solving two equations in two unknowns (use substitution as before)
Check this against the results in our example (and use it for problems!)
28. 28 The general n-firm Cournot case Keep the general case assumptions but assume there are n firms
Nash equilibrium solution procedure the same
But now there are lots of simultaneous reaction functions to deal with
It can be shown that the amount produced by each firm i is
The interesting thing is that the market price is
So, as n ? infinity, P* ? C [because a/(n+1) ? 0 and n/(n+1) ? 1]
In the limit, the same result as price competition!
In mass, homogenous-good markets with lots of small competitors, firms earn zero profit
29. 29 Competition in quantities = “Cournot” 2 Possible scenarios:
Quantity decisions have to be made a long time before sale
Firms choose the quantity they want to produce without knowledge of others’ choices
After supply is determined, there is a “market mechanism” that finds the price at which Demand equals that available Supply
Firms can limit their capacities
Firms choose their capacity without knowledge of others’ choice of capacity
Once they see each others’ capacity, they each charge the market clearing price
30. 30 The Role of Tough Commitments
31. 31 Quantity Pre-commitments Reaction curves are downward sloping
The more F1 expects F2 to produce, the less F1 wants to produce
F2 should pre-commit to producing more than it would otherwise want to
Example: Investing in mass-production equipment
Such pre-commitments cause rivals to back off and “accommodate” by producing less
When are quantity increases credible?
Reputation for high quantity
Large supply or purchase contracts
Cost leadership: investments in lower unit production costs
Irreversible capacity investments
32. 32 Tough quantity competition
33. 33 Pre-commitments A tough commitment means that F2 wants to produce more, at every output level of F1’s: the best response curve is shifted up.
The commitment moves the equilibrium from A to B.
CAREFUL! The commitment is only worth it if the firm earns more at B (after paying for the commitment) ? you have to check.
34. 34 Pre-Emption Commitments change the game: now one or the other will try to commit
Either firm may commit...
But what happens if you can commit first?
Other firm observes your action before choosing their own:
?You gain a first-mover advantage
35. 35 Case: Memory Chips Early 1980s: market dominated by US firms
mid 1980s: Japanese firms (Toshiba, NEC) increased their investment in new capacity (while US firms didn’t)
late 1980s: 80% of market controlled by Japanese firms
1990s: massive investments by South Korean firms (Samsung, Hyundai) while the Japanese firms have not invested
36. Commitment and choosing capacities: If capacities have to be chosen simultaneously, choose to build a plant whose capacity = Cournot quantity
BUT
If one firm can choose capacity first, and can make sure the other firm sees its choice:
The second firm to build will choose its “best response” to the first firm’s capacity
The first firm can profit by making a tough commitment in capacities: build a large plant
Both firms want to be first
There may be a “race” to build first
37. 37 Pre-emptive capacity building
If firms were building at the same time, F2 would build a plant with capacity equal to the Cournot quantity Qc
But if F2 builds first, it will build a larger capacity Q2
38. 38 Strategies to dampen competition
39. 39 Return to price competition Even with only two firms P = MC
This is a very bad position in which to find yourself
What can be done? Try to change the game!
Merge (and earn monopoly profits)
Differentiate your products (a common solution)
Obtain a cost advantage (see Gans, p. 148 – 151)
Collude (illegal and, in any event, hard to make work)
40. 40 Niche market differentiation Go back to price (Bertrand) competition example
Assume buyer demand is horizontal at $1000(perfectly elastic)
Suppose F1 can alter the design of its product
The new product appeals to 40% of the market
These customers are willing to pay a $50/unit premium for this product
MC of this product is $225 ($25 more expensive)
Old product must be retired
41. 41 Analysis F1 wishes to go to the new design
Under old design, P1 = MC = 200
With new design, F1 can post P1 = 250
400 units sold
?1 = (250 – 225)400 = 10,000
What is F2’s best response?
Since P1 > 200, F2 can post P2 > 200 as well
For example, P2 = 201, ?2 = (201 – 200)600 = 600
What is Nash equilibrium?
P2 = 201 ? P1 = 251
So this is not Nash
42. 42 Equilibrium in niche markets Calculating Nash is beyond the scope of this class
Instead, look for undercut proof outcome
Price difference must be $50,
Any more and the 400 customers switch to F2
Any less and F1 could earn more by raising price
F1 must earn same or more profit as what could be obtained by undercutting P2 slightly
If P2 > 200, F1 can always
Keep the old product
Set P1 slightly below P2 and
Get 100% of the market
So, P2 cannot be too high, otherwise this option will be preferred
43. 43 Compute the equilibrium The two requirements imply, respectively
P1 = $50 + P2
(P1 – 225)400 = (P2 – 200)1000
Substitute first requirement into second
P1 = 800/3 ? 267
P2 = 650/3 ? 217
44. 44 Cooperation Collusive Pricing: Can firms collude without communicating?
45. 45 Large Electric Turbine Generators 1950s: three producers of large electric turbine generators in the US
GE, Westinghouse and Allis-Chambers
Lots of profits: low rivalry, high entry barriers
Seem to maintain high prices during the 1950s
Subject of antitrust investigation
But how did collusion take place when there was no evidence of communication (let alone an agreement)
46. 46 Celestial Coordination Competition on tenders from electricity utilities
A formal solicitation of bids was released
Based on the time of the formal document, each firm would consult the lunar calendar
Days 1-17 of lunar month: GE would “own” the contract (high bid with others bidding higher)
Days 18-25: Westinghouse’s turn
Days 26 to 28: A-C’s turn
Gave market shares of 60%, 30% and 10% respectively.
Why did A-C put up with this? Couldn’t be taken to court for breaking a contract. That contract would be illegal.
47. 47 Tacit collusion When interactions occur over many periods, firms can implement a wide range of outcomes
Stay with price competition example
Assume game is repeated indefinitely
Firms have discount rate r
Best case for firms is to post monopoly price
Split market
Split monopoly profit
Problem: strong incentive to cheat (shave price)
Can this be overcome in repeated case?
48. 48 Collusive strategies Consider this dynamic strategy
Set price = $600 (monopoly price w/P = 1000 – Q)
If opponent’s price was $600 this period, set price = $600 next period
If opponent’s price was not $600 this period, set price = $200 forever
Both firms adopt this ‘grim trigger’ strategy
Does either wish to deviate?
49. 49 Can F1 deviate profitably? Assume F2 follows the previous strategy
If F1 also follows the strategy
It gets (600 – 200)200 = 80k forever
So, the PV of following the strategy is 80k/r
Instead, F1 can undercut
If it posts P1 = 599, ?1 = (599 – 200)401 ? 160k
But, in all following periods, P2 = 200 (by the strategy)
The best response in those periods is P1 = 200
So, F1 gets ?1 = 0 forever following a deviation
It is not profitable to deviate from the strategy when
If firms are “sufficiently patient,” collusion can be sustained
50. 50 Cooperation in repeated interactions The previous type of result holds in most repeated situations
That is, cooperation can be sustained in repeated transactions – even though there are incentives to act opportunistically
By cooperating, firms split the best outcome profit
By deviating, a firm gets the short-run benefit but, when cheating is detected, play enters a “punishment” phase
Punishment in future periods more effective with low discount rates(cheater’s lost future benefits have greater value)
There are many cases where “reputation” may be important
Commitment issues (playing “tough” with entrants)
Delivering high quality products (avoiding lemons problems)
Delivering agreed upon effort in strategic alliances (no free riding)
Even Prisoners’ dilemma can be resolved
51. 51 Co-opetition: Commitments that Facilitate Collusion Most Favoured Customer Clause (MFC)
Manufacturers of antiknock petrol additives (Du Pont, Ethyl) were brought before the US Federal Trade Commission for using MFCs.
The seller will pay buyers the best price they pay to anyone.
Commits to not offering selective discounts to attract customers from rivals
Lowers the gain from cheating on price collusion.
“Meet the competition” clauses
With rebates, you find out quickly about cheating
Commitment makes the price war more bitter
Loyalty Programs
harder to cheat by stealing customers from others You can read more about these in Coopetition.You can read more about these in Coopetition.
52. 52 Trigger price strategies In some environments, you can’t tell who has cheated:
Several firms
You don’t see how much they’ve sold
Variable demand ? when your price falls, you don’t know if it’s because demand fell, or someone cheated.
Results in this environment:
We can’t collude at monopoly prices, because cheating is too tempting ? we have to charge mid-range prices
There is a “trigger price”: if the price falls below this trigger, we all revert to competition for a few periods (=punishment), then we cooperate again.
53. 53 Tacit collusion If you can’t talk to each other, how do you agree on a price?
Focal point = something people gravitate to
If the firms are identical, and can sustain collusion at monopoly price, that seems like an obvious focal point
But usually firms have different costs, slightly different products ? how do you coordinate?
Or you might have to charge a mid-range price (as in trigger strategies)
? what price should you charge? How do you reach agreement?
One tactic: Raise your price, hope the others follow
Explains why it’s easier to coordinate on not cutting prices, than on raising prices
(inflation is the customer’s friend!)
54. 54 Ethics of tacit collusion If customers are better off because of collusion, seems ethically defensible
Ex: If firms compete Bertrand, one will leave the market, and the other will charge monopoly prices
Customers are better off with two firms colluding, but only if they’re charging mid-range prices (rather than monopoly prices)
“no price wars”
But such cases are fairly rare
What about in the other situations?
55. 55 Why do you need to know? Suppose you’re entering a market with 3 or 4 producers.
If they’re competing with very similar products, that’s a pretty competitive market
you would expect that prices won’t fall drastically when you enter the market
You enter so long as your marginal cost is less than the going price.
But if they’re colluding:
The price could fall drastically after you enter, if they don’t collude with you, or if there are now too many players to sustain collusion
The going price is not enough information
How would you pick up whether they’re colluding?
Prices that don’t change, when costs or demand changes
In some mkts, occasional price wars when prices go way down.