How does the number and power of firms in a market shape prices, choice and competition?
Market structures: the characteristics of perfect competition, monopolistic competition, oligopoly and monopoly, and their effects on price, output, choice and efficiency.
An SQA Higher Economics answer on market structures, covering the spectrum from perfect competition through monopolistic competition and oligopoly to monopoly, the characteristics of each, and their effects on price, output, consumer choice, efficiency and barriers to entry.
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What this key area is asking
The SQA wants you to place real markets on a spectrum from perfect competition to monopoly, describe the characteristics of each structure, and explain how those characteristics affect price, output, choice and efficiency. You should be able to compare structures and judge their consequences for consumers, which is where the higher-mark "compare" and "evaluate" questions sit.
The spectrum of market structures
Markets are classified by four features: the number of firms, whether the product is identical or differentiated, the height of barriers to entry, and the firm's pricing power.
Perfect competition
Because firms are price takers and entry is free, any abnormal profit attracts new entrants whose extra supply competes the price down, so in the long run firms make only normal profit. Perfect competition delivers low prices and productive efficiency but offers no product choice and leaves no surplus for research. It is a theoretical benchmark that real markets only approach (for example some agricultural or financial markets).
Monopolistic competition and oligopoly
Monopolistic competition has many firms selling slightly differentiated products (different brands of coffee shop or hairdresser). Differentiation gives each firm a little pricing power and a downward-sloping demand curve, but low barriers mean long-run profits are competed away. Non-price competition (branding, service, location) matters.
Oligopoly is a market dominated by a few large firms that are interdependent: each must consider how rivals will react to its decisions. Barriers to entry are high. Firms often avoid price wars and compete instead through advertising, loyalty schemes and product features (non-price competition). There is a risk of collusion, where firms act together like a monopoly to raise prices, which competition law forbids.
Monopoly
Comparing the structures
| Feature | Perfect competition | Monopolistic competition | Oligopoly | Monopoly |
|---|---|---|---|---|
| Number of firms | Very many | Many | Few | One dominant |
| Product | Identical | Differentiated | Similar or differentiated | Unique |
| Barriers to entry | None | Low | High | Very high |
| Pricing power | Price taker | Some | Considerable | Price maker |
| Long-run profit | Normal | Normal | Can be abnormal | Abnormal |
Worked example: judging a proposed merger
Why market structures matter
Market structure determines how much firms can charge, how efficient they are, how much choice and innovation consumers get, and whether a market needs regulation. It links costs and economies of scale (why some industries concentrate) to market failure and government intervention (why monopolies are regulated), tying the whole microeconomics unit together.
Try this
Q1. State two characteristics of a perfectly competitive market. [2 marks]
- Cue. Any two of: very many small firms; an identical (homogeneous) product; no barriers to entry or exit; firms are price takers; perfect knowledge.
Q2. Explain one advantage and one disadvantage of monopoly for consumers. [4 marks]
- Cue. Advantage: large economies of scale and abnormal profits can fund research and lower long-run costs. Disadvantage: with no competition the monopolist can restrict output and charge a higher price, reducing consumer choice and welfare.
Exam-style practice questions
Practice questions written in the style of SQA exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.
SQA Higher (style)6 marksCompare the characteristics of perfect competition and monopoly.Show worked answer →
Worth 6 marks. Reward genuine comparison across number of firms, products, barriers and pricing power.
Number of firms and products (about 2 marks). Perfect competition has very many small firms selling an identical (homogeneous) product, so no firm has market power. A monopoly is a single dominant firm that is the sole, or near-sole, supplier of a product with no close substitutes.
Barriers to entry and price (about 2 marks). Perfect competition has no barriers to entry, so firms can freely enter and leave; the monopoly is protected by high barriers (legal protection, control of a resource, huge economies of scale) that keep rivals out. The competitive firm is a price taker, accepting the market price, while the monopolist is a price maker, able to set price by restricting output.
Effects on consumers (about 2 marks). Perfect competition tends to give lower prices, no abnormal long-run profit and productive efficiency, but little choice (identical goods) and no funds for innovation. Monopoly can charge higher prices and restrict output, harming consumers, though it may use its profits and economies of scale for research and development. The contrast is the standard high-mark answer.
SQA Higher (style)6 marksExplain how barriers to entry allow a monopoly to earn long-run abnormal profit.Show worked answer →
Worth 6 marks. Define barriers, give types, and link to sustained profit.
The role of barriers (about 2 marks). Barriers to entry are obstacles that prevent new firms from entering a market. Without them, abnormal profit would attract new entrants whose extra supply would compete the price down. Barriers stop this, so the incumbent keeps its profit.
Types of barrier (about 2 marks). Barriers include legal protection (patents, licences), control of an essential resource or distribution network, very high start-up or sunk costs, and huge economies of scale that let the incumbent undercut any new entrant. Strong brand loyalty built by advertising can also deter entry.
The result (about 2 marks). Because rivals cannot enter, the monopolist can restrict output and hold price above the competitive level, earning abnormal profit year after year. This is why competition authorities regulate monopolies and try to lower barriers, to protect consumers from sustained high prices and restricted output.
Related dot points
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An SQA Higher Economics answer on production and costs, covering production and productivity, the difference between fixed and variable costs, total, average and marginal cost, total and average revenue, the meaning of profit, and economies and diseconomies of scale.
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An SQA Higher Economics answer on market failure and intervention, covering negative and positive externalities, public goods, merit and demerit goods, monopoly power and information failure, and the government responses of taxes, subsidies, regulation, provision and information campaigns, with their limitations.
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An SQA Higher Economics answer on the theory of supply, covering the law of supply and why the supply curve slopes up, the difference between a movement along the curve and a shift, and the non-price determinants of supply such as costs of production, technology, taxes and subsidies, and the price of other goods.
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Sources & how we know this
- Higher Economics Course Specification — SQA (Qualifications Scotland) (2024)