Category Archives: Market Structures

The New Corporation – Documentary

Following on from the very successful documentary ‘The Corporation’ comes ‘The New Corporation’. The Corporation​ examined an institution within society. THE NEW CORPORATION reveals a society now fully remade in the corporation’s image, tracking devastating consequences and also inspiring movements for change. Click on the link below to view screening options – The New Corporation

New Zealand Supermarket Duopoly – maximax and maximin strategies

Michael Cameron did a very relevant post on his blog ‘Sex, Drugs and Economics’ which focused on the duopoly market structure of New Zealand’s supermarkets. Part of the NCEA Level 3 and the CIE A2 economics courses look at market structures – monopolistic, oligopoly, duopoly, monopoly, and monopsony. A duopoly refers to two firms in a market whilst an oligopoly has a small number of firms but greater than two. Therefore we can say that Oligopoly and Duopoly are very similar market structures and they can co-ordinate their behaviour to exploit the market by lowering competition which in turn leads to greater profits for all.

Using the example of the supermarket duopoly Foodstuffs and Woolworths. Each company has two options – high price or low price. Obviously if they both price low they stand to be worse off and if they price high they are both set to gain. The outcome and payoffs are illustrated below:

Maximax – riskier strategy
A maximax strategy is one where the player attempts to earn the maximum possible benefit available. This means they will prefer the alternative which includes the chance of achieving the best possible outcome – even if a highly unfavourable outcome is possible. This strategy, often referred to as the best of the best is often seen as ‘naive’ and overly optimistic strategy, in that it assumes a highly favourable environment for decision making.

In this case, for both food providers, the aggressive maximax strategy is $140m from a low price and $120m from a high price, so a low price gives the maximax pay-off.

Maximin – conservative strategy
A maximin strategy is where a player chooses the best of the worst pay-off. This is commonly chosen when a player cannot rely on the other party to keep any agreement that has been made – for example, to deny.

In terms of the pessimistic maximin strategy, the worst outcome from a low price is $100m, and from a high price is $70m – hence a low price provides the best of the worst outcomes.

Again, lowering price is the dominant strategy, and the only way to increase the pay-off would be to collude and increase price together. Of course, this requires an agreement, and collusion, and this creates two further risks – one of the food companies reneges on the agreement and ‘rats’, and the competition authorities investigate the food companies, and impose a penalty.

Nash equilibrium
Nash equilibrium, named after Nobel winning economist, John Nash, is a solution to a game involving two or more players who want the best outcome for themselves and must take the actions of others into account. When Nash equilibrium is reached, players cannot improve their payoff by independently changing their strategy. This means that it is the best strategy assuming the other has chosen a strategy and will not change it. For example, in the Prisoner’s Dilemma game, confessing is a Nash equilibrium because it is the best outcome, taking into account the likely actions of others.

NCEA Level 3 and CIE A2 Economics – Natural Monopoly

Natural Monopoly-Features

A natural monopoly is when one firm has the ability to supply the entire market at lower prices than two or more firms. A natural monopoly faces downward-sloping average cost (AC) for the entire range for which demand is applicable. The reason for its downward-sloping AC curve is usually that the initial investment in the infrastructure of the firm is large, but once it is in place, the marginal cost (MC) of production is low, for example hydro power. This high establishment cost is a strong barrier to entry and a natural monopoly could undercut any would-be competitor so they could not survive. Natural monopolies often involve some kind of network, for example water, gas,phone, rail.

Equilibrium Output-Natural Monopoly

The rule for maximising profit or minimising a loss (the equlibrium) for a natural monopoly is the same as any other firm. The most profitable output or smallest loss is where marginal revenue (MR) equals marginal cost (MC). Any other position will result in a smaller profit or greater loss. Therefore, the equilibrium output is at a price of Pe and quantity Qe (determined from the intersection of the marginal cost and marginal revenue curves). At the equilibrium output Qe the natural monopoly is making a supernormal profit (of $100m) and produces less than what society or consumers desire. Operating at the equilibrium output position creates a deadweight loss of BFG because consumer surplus and producer surplus are not maximised. The natural monopoly is charging a price in excess of marginal cost (P > MC), this is called mark-up pricing. At the equilibrium output in perfect competition, price and marginal cost are the same. Sellers cannot charge higher prices because they would immediately lose sales to competitors. This is called marginal cost pricing and occurs in perfect competition where at the equilibrium output position price equals marginal cost (P = MC). A natural monopoly charges more and produces less than would be the case if the firm operated as a perfect competitor. Overpricing and not operating at the allocatively efficient (socially optimum) level means that a natural monopoly can be seen as socially undesirable. However, if consumers are not subject to competitive advertising and marketing, they receive the good or service at cost and the firm carries out R & D (research and development) a natural monopoly can be viewed as socially desirable. A natural monopoly may also be seen as socially desirable because it is wasteful to duplicate the existing infrastructure, so encouraging competition is seen as undesirable. If output is below equilibrium Qe (where MR equals MC), the firm would be missing out on marginal profits because the revenue from producing the last article is greater than its cost of production, implying that the firm could increase output and increase profit. However, increasing output beyond Qe reverses the position. The firm will be making marginal losses because the revenue from one additional article is now less than the cost of its production. If increased output adds more to cost than to revenue, a firm has obviously passed the point of maximum profit (or minimum loss). Price discrimination may be practised by any monopolist. This is where they segment the market in some way, for example domestic and industrial users may be charged at different rates. A two-part tariff is a system where users are charged a fixed amount for a given time period and per unit charge for use, for example with the phone there is a line rental and a charge for toll calls. Off-peak pricing is a system of charging that results in a higher price at peak time usage than at off-peak times, for example toll calls made after 6 p.m. are at a cheaper rate.

Read more at: elearn Economics –

A2 Economics – Differing objectives of firms

With the CIE A2 essay paper on Wednesday here are some notes on the differing objectives of firms. This could be the second part of an essay question with the first part potentially being about market structures – perfect and imperfect competition.

The standard neo-classical assumption is that a business seeks to maximise profits (MC=MR) from producing and selling an output in a market. However, there are other objectives that firms might decide to pursue and this has implications for price, output and economic welfare. Furthermore, it is sometimes difficult for firms to identify their profit maximising output because they cannot accurately calculate marginal revenue and marginal costs. Any company has various interest groups that have stakes in the company. These include employees, managers, shareholders and customers.

Each of these groups is likely to have different objectives or goals. What the managers want to do is not necessarily what the owners want them to do. Managers may have a lot of freedom to pursue their own objectives rather than those of the shareholders and may try to maximise their own utility rather than the profit levels of the company. Shareholders may not keep themselves well informed and therefore rely on the decision making of the managers of the company.

The dominant group at any moment in time can give greater emphasis to their own objectives, for example, the main price and output decisions may be taken at local level by managers, with shareholders taking only a distant view of the company’s performance and strategy. Below are some other objectives:

Satisficing – with all the interest groups in a company all with their own objectives (higher wages for employees, customer satisfaction, marketing, etc) the overall objectives of a company are the result of discussion, negotiation and bargaining with all these groups. The result of this is likely to be a compromise between parties that does not maximise anything, this is satisficing.

Market share – some firms may be motivated by increasing market share. This is prevalent when firms operate in markets with a few large competitors and try to attract new customers from other competitors.

Survival – some firms look at survival, – especially those new to a highly competitive market. Surival is also prevalent when an economy goes through a downturn and consumer spending falls throughout the economy.

Shareholder value – increase shareholder value means to increase the asset value of the business. Shareholder value is defined as the remaining value of the business once all debts have been paid.

Ethical goals – increasingly, firms are introducing ethical goals such as those associated with the environment and carbon emissions, and with fair trade. This may mean more investment into these goals that leads to a higher cost structure. However, advertising ethical goals to consumers could attract more demand.

Limit pricing – firms may adopt predatory pricing policies by lowering prices to a level that forces any new firms entering the industry to operate at a loss. This allows firms to sustain a monopoly position in a market.

Sales volume maximisation – firm might wish to maximise the number of units sold, in turn maximising its share of the market, although this goal would have to be pursued subject to a profit constraint. The firm could expect to sell a large number of units if it dropped its price far enough, but at some point cutting price any further will involve making a loss. The output and price of a firm that wishes to maximise sales is subject to the constraint of making at least normal profit. Therefore output is set at the level where AR = AC. See graph below.

Sales revenue maximisation – total revenue is maximised when Marginal Revenue = zero (MR = 0), shown on the graph below. The shareholders of a business may introduce a constraint on the price and output decisions of managers, this is known as constrained sales revenue maximisation. Shareholders may introduce a minimum profit constraint designed to underpin the market valuation of their shares and maintain a dividend (a share of the company’s profits).

Read more at: elearn Economics –

A2 Economics – Contestable Markets

I covered this topic today at the Cambridge A2 Economics revision course. The degree of contestability of a market is measured by the extent to which the gains from market entry for a firm exceed the cost of entering (i.e. the cost of overcoming barriers to entry), with the risks associated with failure taken into account (the cost associated with any barriers to exit). Accordingly, the levels of barriers to entry and exit are crucial in determining the level of a market’s contestability. Barriers to exit consist of sunk costs, that is to say costs that cannot be recovered when leaving the market. The contestable markets approach suggests that potential entrants consider post‑entry profit levels, rather than the pre-entry levels suggested by neo‑classical theory.

Obviously no market is perfectly contestable, i.e. with zero sunk costs. In modern economies it is the degree of contestability which is relevant, some markets are more contestable than others. Also just because there have been no new entrants to a market over a given period of time does not mean that this market is not contestable. The threat of entry will be enough to make the existing (incumbent) firms behave in such a way as to recognise this, i.e. by setting a price which doesn’t attract entry and which only makes normal profits.

Markets which are highly contestable are likely to be vulnerable to ‘hit and run competition’. Consider a situation where existing firms are pricing at above the entry‑limit level. Even in the event that existing firms react in a predatory style, new entry will be profitable as long as there is a time lag between entry and the implementation of such action. Having made a profit in the intervening period, the new entrant can then leave the market at very little cost.

In a contestable market there are no structural barriers to the entry of firms in the long-run. If existing businesses are enjoying high economic profits, there is an incentive for new firms to enter the industry. This increases market competition and dilutes monopoly profits for the incumbent firms. Market contestability requires there are few sunk costs. A sunk cost is committed by a producer when entering an industry but cannot be recovered if a firm decides to leave a market.

Entry limit pricing

The fear on the part of existing firms of rendering the market contestable (stimulating new entry) by making high levels of profit is likely to lead to the adoption of entry limit pricing, a concept introduced in the previous unit. This is essentially a defensive strategy, with existing firms setting prices as high as possible but not so high as to enable new corners to enter the industry. If the existing firms set price at P2 and output at Q2 (see diagram below), it would be possible for a new firm to enter the industry and supply Q1. Total market supply would then be Q3 (Q1 + Q2), the price would be P3 and the new firm would be covering its costs. If, instead, the existing firms chose to produce at Q3 (with price level P3), the new firm producing Q1 (total market supply would now be Q4 at price P4) would not be covering its costs and would have to exit the industry in the long run.

The video below on the Airline Industry in the US from Commanding Heights series is a good example of breaking down monopoly power.


Anforme – A2 Level Economics Revision Booklet.

Does a higher minimum wage mean higher unemployment?

In most economics textbooks the labour market is shown with a simple graph of the supply of labour and the demand for labour and where they intersect the wage that employees receive for their service and the amount employed. The theory is based on the following:

Demand for Labour
In this context the demand for labour is determined by the marginal revenue product where workers are paid the value of their marginal revenue product to the firm. The demand for labour is downward sloping as when there is a fall in the wage rate the firm will expand employment as the labour input has become relatively cheaper for a given level of productivity, compared to other inputs. A rise in the wage rate will causes a contraction of labour demand.

Supply of Labour
Economic theory would suggest that the real wage (adjusted for inflation) is a key determinant of the number of hours. Therefore the supply curve for labour slopes upward because people want to work more hours if you pay them more, at least in theory. An increase in the real wage on offer in a job should lead to someone supplying more hours of work over a given period of time, although there is the possibility that further increases in the going wage rate might have little effect on an individual’s labour supply.

The Minimum Wage

The minimum wage distorts the market equilibrium as there is now a wage floor – a level which the wage cannot fall below. If the minimum wage is below the equilibrium wage then there is no impact as the market will ensure that is reaches equilibrium. However a minimum wage above the equilibrium means that companies will hire fewer workers and therefore result in more unemployment. On the graph below a minimum wage of W1 means that the level of employment has fallen but those prepared to work but are involuntary unemployed has increased. However the people still employed are better off as they are paid more for the same work; their gain is exactly balanced by their employers’ loss. The jobs that someone would have been willing to do at less than the wage of We and for which some company would have been willing to pay more than We. Those jobs are now gone, as well as the goods and services they would have produced.

Real Impact of the Minimum Wage.

In reality the theory of the minimum wage explained above is not as simple as it is made out to be. From records in the USA there is no obvious relationship between the minimum wage and unemployment: adjusted for inflation, the federal minimum wage was highest from 1967 through 1969, when the unemployment rate was below 4%. One study in 1994 by David Card and Alan Krueger evaluated an increase in New Jersey’s minimum wage by comparing fast-food restaurants on both sides of the New Jersey – Pennsylvania border. They concluded, “contrary to the central prediction of the textbook model … we find no evidence that the rise in New Jersey’s minimum wage reduced employment at fast-food restaurants in the state.”

The idea that a higher minimum wage might not increase unemployment goes against the the theory in textbooks as if labour becomes more expensive firms will take on less employees. But there are several reason why this might not be the case:

  • The standard model states that firms will replace labour with machines if wages increase, but what happens if labour saving technologies are not available at a reasonable cost.
  • Some employers may not be able to maintain their business with fewer workers especially in service based industries. Therefore, some companies can’t lay off employees if the minimum wage is increased.
  • Small firms are traditionally labour intensive and can’t afford large capital investment. Therefore the minimum wage doesn’t have the impact of laying off workers.
  • If employers have significant market power that the theory of the supply and demand for labour doesn’t exist, then they can reduce the wage level by hiring fewer workers (only those willing to work for low pay), just as a monopolist can boost prices by cutting production (think of an oil cartel, for example, see graph Monopsony Labour Market). A minimum wage forces them to pay more, which eliminates the incentive to minimize their workforce.
  • Even though a higher minimum wage will raise labour costs many companies can recoup cost increases in the form of higher prices; because most of their customers are not poor, the net effect is to transfer money from higher-income to lower-income families. In addition, companies that pay more often benefit from higher employee productivity, offsetting the growth in labor costs.
  • Higher wages boost productivity as they motivate people to work harder, they attract higher-skilled workers, and they reduce employee turnover, lowering hiring and training costs, among other things. If fewer people quit their jobs, that also reduces the number of people who are out of work at any one time because they’re looking for something better. A higher minimum wage motivates more people to enter the labor force, raising both employment and output.
  • Higher pay increases workers’ buying power. Because poor people spend a relatively large proportion of their income, a higher minimum wage can boost overall economic activity and stimulate economic growth, creating more jobs.
Monopsony Labour Market

All the above add a range of variables that are not considered in the simple supply and demand model for labour. It maybe useful as a starting point in discussing the minimum wage but has its limitations in the more complex real world

Source: Economism by James Kwak

A2 Economics – Concentration Ratio

Part of the CIE A2 syllabus deals with the concentration ratio and by good fortune a recent edition of The Economist schools brief looked at this area.

The concentration ratio is the percentage of market share taken up by the largest firms. It could be a 3 firm concentration ratio (market share of 3 biggest) or 5 firms concentration ratio. Concentration ratios are used to determine the market structure and competitiveness of the market. The most commonly used are 4, 5 or 8 firm concentration ratios which measure the proportion of the market’s output provided by the largest 4, 5 or 8 firms.

Example of a hypothetical concentration ratio
The following are the annual sales, in $m, of the six firms in a hypothetical market:

Firm A = 56
Firm B = 43
Firm C = 22
Firm D = 12
Firm E = 3
Firm F = 1

In this hypothetical case, the 3-firm concentration ratio is 88.3%, that is 121/137 x 100.

According to the OECD, member countries between 2000 and 2014 experienced an increase in concentration ratios. The share of sales accounted for by the top eight firms in a given industry in the EU and North American were as follows:

Some policy makers are unconcerned with industrial concentration as it doesn’t tell you how competitive the market is for a particular good. Although others have blamed falling levels of competition, the stagnant labour markets and growing inequality. Add to that low interest rates and weak investment the rising power of companies has been increasing.

However one could argue that those firms which have high concentrations (especially in the technology sector) have also been very productive. The internet has broken down barriers to entry into markets and enabled firms to deliver goods and services in a very convenient manner at lower prices to a vast consumer market. But although this sounds encouraging there are barriers to new firms entering into this medium:

  • a new firm will require masses of data to tailor their services to individual users
  • other firms already in the market can see what preferences consumers have and because they already have a client base they can easily provide similar products/services.
  • established firms already in the market can buy out new entrants – Facebook bought Instagram and WhatsApp. Between 2009-2019 technology firms made over 400 acquisitions with little interference from regulators.

Source: The Economist – Economics brief – Competition. 8th August 2020

Oligopoly – Game Theory and Dominant Strategy

Been covering this topic with my A2 class and found Jason Welker’s video very good at explaining Prisoner’s Dilemma and the dominant strategy.

In recent years game theory has become a popular way of examining the strategies that oligopolists may adopt in a market. Game theory involves studying the alternative strategies oligopolists may choose to adopt depending on their assumptions about their rivals’ behaviour. Put at its simplest, if a firm is considering reducing its price, in making its decision it will need to take into account how its rival oligopolists might react and how it will affect them. Firms can choose high risk or low risk strategies in what is very similar to a game of poker between four or five players.

Although game theory strategy involves some extremely difficult maths the A2 Economics course concentrates on relatively straightforward two-player zero-sum games where one player’s gain must equal the other player’s loss.

Ludicrous regulations of the US Airline Industry and Contestable Markets

With Auckland now at COVID-19 Alert Level 3 and schools operating online we continued going through the A2 syllabus and discussed Contestable Markets using Webex. I used this clip from Commanding Heights to show how regulated the US airline industry was during the 1970’s. Regulations meant that major carriers like Pan Am never had to compete with newcomers. However an Englishman named Freddie Laker was determined to break this tradition and set-up Laker airways to compete on trans-atlantic flights. He offered flights at less than half the price of what Pan Am charged. Alfred Kahn was given the task by the then President Jimmy Carter to breakup the Civil Aeronautics Board (the regulatory body) and he wanted a leaner regulatory environment in which the market was free to dictate price. There is a piece in the clip that shows how ludicrous some of the regulations were:

When I got to the Civil Aeronauts Board, the biggest division under me was the division of enforcement – in effect, FBI agents who would go around and seek out secret discounts and then impose fines. We would discipline them. It was illegal to compete in price. That means it was illegal to compete in the discounts you offer travel agents. So we regulated travel agents’ discounts. Internationally, since they couldn’t cut rates, they competed by having more and more sumptuous meals. We actually regulated the size of sandwiches. Alfred Kahn

When the CAB was closed down competition was the rule and the industry had vastly underestimated the demand for air travel at lower prices – a very elastic demand curve – see graph below.

In the A2 course contestable markets is a popular essay question and is usually combined with another market structure.

What is a contestable market?

• One in which there is one firm (or a small number of firms)
• Because of freedom of entry and exit, the firm faces competition and might operate in a way similar to a perfectly competitive firm
• The threat of “hit and run entry” from new firms may be sufficient to keep the industry operating at a competitive price and output
• The key requirement for a contestable market is the absence of sunk costs – i.e. costs that cannot be recovered if a business decides to leave a market
• When sunk costs are high, a market is more likely to produce an price and output similar to monopoly (with the risk of allocative inefficiency and loss of economic welfare)
• A perfectly contestable market occurs only when entry and exit into and out of a market is perfectly costless
• Contestable markets are different from perfect competitive markets
• It is possible for one incumbent firm to dominate the industry
• Each existing firm in the market produces a differentiated product (i.e. goods and services are not perfect substitutes for each other)

There are 3 conditions for market contestability:

• Perfect information and the ability and or legal right to use the best available technology
• Freedom to market / advertise and enter a market
• The absence of sunk costs

• Liberalisation of the US Airline Industry in the 1970’s and the European Airline Market in late 1990s
• Traditional “flag-flying” airlines faced new competition
• Barriers to entry in the industry were lowered (including greater use of leased aircraft)
• New Entrants – easyJet- Ryanair