Skip to main content

Exercise: Payoff matrix -Oligopoly market-

You are given a payoff matrix for two firms in an oligopoly market.

  • Find the dominant strategy (if any) for each firm.
  • What profit would they each earn if they form a cartel (if possible)?
  • Can the cartel hold in the long run? If not, what is the long run equilibrium?

Payoff Matrix: Firm A: high prices Firm A: low prices
Firm B: high pricesA: $1000
B: $1000
A: $1200
B: $800
Firm B: low pricesA: $600
B: $1200
A: $700
B: $700

The dominant strategy for firm A is to charge a low price for its product. You can see that no matter what firm B chooses, firm A is always better off by choosing the low price option (i.e its profit is always bigger than if it had charged a high price).

The strategy for firm B depends on the choices firm A makes. If firm A charges a high (low) price then firm B should charge a low (high) price.

In order to find the point at which the firms would collude (i.e act as one monopolistic firm), find the point(s) where the sum of economic profits is the greatest. Then choose the points that benefit both parties. In our case we see that the sum of the first entries in each column are equal to one another and greater than the rest of the sums in each entry in the matrix. As we will see, the long run equilibrium prevents the firms from colluding.
  • Since we know that the firm A will charge a low price, it makes sense for firm B to charge a high price in order to maximize its profit. Then, we see that the long run equilibrium is in the upper right entry of the payoff matrix. Firm A has no incentive to form a cartel with firm B. 

Reference: Exercise inspired by: Mayer,David. AP Microeconomics Crash Course. Research & Education Association (2014). p 123. 

Comments

Popular posts from this blog

Microeconomics: Shift in Supply

We recently talked about the factors that cause a shift in the demand. It is now time to discuss the factors that shift the supply curve which cause the equilibrium price and demand to change. Determinants of Supply: changes in supply are caused by changes in the price of inputs, the number of firms in the market, technology, changes in the price of related goods and services, and changes in expected prices. An increase (decrease) in the price of an input results in less (more) supply as per unit production costs rise (fall). More competition increases supply, and less competition leads to less supply. If a new firm enters the market for good X, then the supply of good X increases. Improvement in technology can result in an increase in the ability of producers to supply their products. For example, the invention of the printing press increased the supply of books. An increase (decrease) in the price of a related good leads to an increase (decrease) in the supply of the other...

Macroeconomics: multiplier and crowding out effects

Multiplier effect: whenever   any of the components of AD increases, the increase in GDP will be greater than the initial increase in expenditures. The impact on GDP of a particular increase in spending depends on the proportion of the new income that is taken out of the system to the proportion that continues to circulate in the economy. The multiplier effect tells us the impact a particular change in one the components of AD will have on the total income (GDP).  Let k denote the spending multiplier, which is a function of MPC and MPS. The larger the marginal propensity to consume, the larger the spending multiplier. Notice that the larger the MPC, the greater the impact a particular change in the spending variables will have on the nation's GDP. The crowding out effect: If government spending increases without an increase in taxes, the government must borrow funds from the private sector to finance its deficit, thereby increasing the interest rate. This increase in interest ...

Microeconomics: Firms and cost in the short run

In Economics, the term short run refers to a time period where at least one variable of interest does not change . In our case, the short run for a firm is when at least one input  (labor, land, capital) stays fixed. Usually land and capital are considered fixed in the short run.  If an input is fixed during a period time, no matter how much the total product a firm produces, its cost stays the same. This cost is commonly known as fixed cost (FC). Examples of fixed costs: rent, property taxes, loan payments. Labor is often considered to be a part of the  variable cost (VC) . Variable cost can be defined as the cost a firm has control over during the short run. Unlike fixed cost, variable cost increases (decreases) as a firm's total product increases (decreases). Examples of variable costs include: utility bills, wages, raw materials A firm's total cost (TC) is the sum of its variable and fixed costs. As you can see, the fixed cost...