HSC Economics Topic 3 & 4 2026

The role of the market in an economy is…

to solve the economic problem - that is, we have limited resources but unlimited wants; in other words, resources are scares and they must be allocated efficiently by determining what, how and for whom goods/services are produced.

What are the types of markets?

Product markets, which facilitate the exchange of goods and services, and factor markets, which enable the allocation of resources like labour and capital.

Define derived demand.

Derived demand refers to an increase in demand for a factor of production or intermediate good that occurs as a result of an increase in demand of the finished or other semi-finished goods. That is to say, if more people want orange juice, then the demand for oranges will go up, and that is derived demand.

What do prices indicate in a market?

1. Prices reflect the relative scarcity of goods and services in terms of their supply.

2. Prices help to allocate resources in the production of goods and services which yield the highest returns or profits to producers.

3. Prices act as incentives or signals for producers and entrepreneurs to take risks in organising the factors of production to produce the goods and services demanded by consumers.

4. Prices act as a rationing device in enabling markets to clear.

5. Prices are an equilibrating device in markets. Changes in prices bring about equilibrium between demand and supply if they are in a disequilibrium situation such as a shortage or surplus of goods.

Ceteris Paribus is defined as…

“all other things being equal,” that is, all other external factors being held constant.

The law of demand states that…

ceteris paribus (all other factors held constant), there is an inverse relationship between the price of a good or service and the quantity demanded by consumers. This arises from:

Substitution Effect: When a good's price rises, consumers find it relatively more expensive compared to substitutes, leading them to purchase those alternatives. When the price falls, the good becomes relatively cheaper, encouraging substitution away from alternatives.

Income Effect: A price increase reduces consumers' real income (purchasing power), so they can afford to buy less of the good (and other goods). A price decrease increases real income, allowing consumers to buy more.

Define Individual Demand.

The quantity of a good a single consumer is willing and able to purchase at various prices, given their income, preferences, and the prices of related goods. It is the foundation for the market demand curve.

Define Market Demand.

The sum of all individual demands for a good or service at each price level. It is derived by horizontally summing the individual demand curves. Market demand reflects the total quantity demanded by all consumers in a market.

List the factors that can affect demand.

Price of the Good or Service (Movement Along the Demand Curve)

• Explanation: This is the primary factor. As the price of a good falls, the quantity demanded rises (expansion of demand) and vice versa (contraction of demand). This relationship is represented by a movement along the existing demand curve.

Consumer Income

• Explanation: Changes in consumers' real income (adjusted for inflation) alter their purchasing power.

• Normal Goods: For most goods (normal goods), demand increases as income rises and decreases as income falls. Examples include new cars, restaurant meals, and electronics.

• Inferior Goods: For a subset of goods (inferior goods), demand decreases as income rises and increases as income falls. Examples include generic brands, used goods, and public transportation.

Tastes and Preferences

• Explanation: Changes in consumer preferences, often driven by cultural trends, advertising, fashion, health awareness, or seasonal factors, directly affect demand.

• Examples: Increased health consciousness may raise demand for organic food and lower demand for sugary drinks. Seasonal changes increase demand for winter clothing in cold months.

Prices of Related Goods

• Substitute Goods: Goods that can be used in place of each other (e.g., tea and coffee). If the price of coffee rises, demand for tea increases. The relationship between the price of one good and the demand for its substitute is positive.

• Complementary Goods: Goods that are used together (e.g., cars and petrol). If the price of cars rises, demand for cars falls, which in turn reduces demand for petrol. The relationship between the price of one good and the demand for its complement is negative.

Consumer Expectations

• Explanation: Anticipated future changes in prices, income, or product availability can alter current demand.

• Future Price Expectations: If consumers expect prices to rise sharply in the future (e.g., due to a shortage), they may increase current demand to avoid higher costs later. Conversely, if a price drop is expected, current demand may decrease.

• Future Income Expectations: If consumers expect a future pay rise, they may increase current spending. If a recession is anticipated, they may cut back.

A movement or shift of the supply curve indicates…

Causes:

• Expansion/Contraction: Only a change in the price of the good itself.

• Increase in Demand (rightward shift): Can result from:

  • Increase in consumer income (for normal goods).

  • Increase in the price of a substitute good.

  • Decrease in the price of a complementary good.

  • Change in consumer tastes or preferences in favour of the good.

  • Expected future price increase (encouraging current purchases).

  • Increase in population or number of buyers.

• Decrease in Demand (leftward shift): Can result from the opposite factors: fall in income (for normal goods), fall in substitute price, rise in complement price, change in tastes away from the good, expected future price decrease, or decrease in population.

Implications:

• Expansion/Contraction: Implication is a change in quantity exchanged and market price (along the supply curve). For example, a price cut leads to higher sales volume. No underlying change in consumer conditions has occurred.

• Increase/Decrease: Implication is a fundamental change in consumer behaviour at all price levels. The new equilibrium price and quantity will be different because the entire demand curve has shifted. For example, a rightward shift in demand (increase) leads to a higher equilibrium price and higher equilibrium quantity, assuming supply remains unchanged. A leftward shift (decrease) leads to a lower equilibrium price and quantity. These shifts can also alter consumer surplus, market efficiency, and resource allocation.

The law of supply states that…

ceteris paribus (all other factors held constant), there is a direct (positive) relationship between the price of a good or service and the quantity supplied by producers.

Substitution Effect: When a good's price rises, consumers find it relatively more expensive compared to substitutes, leading them to purchase those alternatives. When the price falls, the good becomes relatively cheaper, encouraging substitution away from alternatives.

Income Effect: A price increase reduces consumers' real income (purchasing power), so they can afford to buy less of the good (and other goods). A price decrease increases real income, allowing consumers to buy more.

Define Individual Supply.

The quantity of a good a single producer is willing and able to supply at various prices, given their revenue, output, and the prices of competitors. It is the foundation for the market supply curve.

Define Market Supply.

The sum of all individual supplies for a good or service at each price level. It is derived by horizontally summing the individual supply curves. Market supply reflects the total quantity supplied by all producers in a market.

List the factors that can affect supply.

Price of the Good or Service (Movement Along the Supply Curve)

• Explanation: This is the primary factor. As the price of a good rises, the quantity supplied rises (expansion of supply); as the price falls, quantity supplied falls (contraction of supply). This is represented by a movement along the existing supply curve.

Costs of Production

• Explanation: Changes in the prices of inputs—labour, raw materials, energy, capital—directly affect the cost of producing a good. When input costs rise, producing the same quantity becomes less profitable, reducing supply at every price. When input costs fall, supply increases.

Producer Expectations

• Explanation: Expectations about future prices significantly influence current supply decisions.

• Example: If farmers expect the price of wheat to rise significantly next year, they may store some of their current harvest to sell later, reducing current supply. Conversely, if a price drop is expected, they may sell more now.

Number of Producers (Market Entry/Exit)

• Explanation: The total number of firms producing a good affects aggregate supply. When more firms enter a market (due to high profits or low barriers), the market supply curve shifts to the right. When firms exit (due to losses or high barriers), supply shifts left.

Technology

• Explanation: Technological improvements allow firms to produce the same output with fewer inputs, lowering costs and increasing supply. New production techniques, automation, and better machinery all shift the supply curve to the right.

What is market equilibrium?

Market equilibrium refers to when the price/quantity at which quantity demanded = quantity supplied (where the demand and supply curves intersect). No shortage, no surplus.

How can market equilibrium be shifted?

When there is a change in supply/demand, whether an expansion, contraction, increase or decrease - the equilibrium point for supply/demand will change to fit the new point sooner or later.

How does the level of competition affect prices and output?

Pricing Strategy:

• In highly competitive markets, firms often have to lower their prices to attract customers. This leads to price competition, where companies strive to offer the lowest prices while still maintaining profitability.

• Conversely, in monopolistic or less competitive environments, firms have more power to set higher prices since consumers have fewer alternatives. This often results in higher markups and reduced consumer welfare.

Output Levels:

• In competitive markets, increased rivalry encourages firms to expand production to meet consumer demand and maximise market share. As more firms enter a market (especially if profits are attractive), overall output increases, benefiting consumers through greater availability of goods or services.

• In contrast, in markets with less competition, firms may produce less output to maintain higher prices. This can lead to inefficiencies and a decrease in overall consumption, as consumers may have fewer choices and face higher prices.

Quality and Innovation:

• An increase in competition often prompts firms to innovate and improve the quality of their products or services. Companies must distinguish themselves in a crowded field, leading to better offerings for consumers.

• With less competition, the incentive for innovation reduces, as firms can rely on their market power to maintain sales without the need to enhance quality or innovate.

Market Entry and Exit:

• The level of competition affects entry and exit barriers in a market. High competition tends to lower these barriers, allowing new firms to enter and challenge the status quo, which can further enhance output and lower prices.

• In contrast, monopolies or oligopolies feature high entry barriers, limiting new entrants and sustaining higher prices and lower output in the long run.

Consumer Choice:

• Competitive markets offer consumers a wider variety of choices. Firms must not only compete on price but also on different features and quality, enhancing consumer satisfaction.

• In non-competitive markets, consumers may face limited options, leading to dissatisfaction as their needs may not be fully met.

What is a price ceiling?

A price ceiling is a government-imposed maximum limit on how high a price can be charged for a product or service. It is typically set below the market equilibrium price to protect consumers from excessively high prices on essential goods and services, such as food, housing, and healthcare. By keeping prices lower, price ceilings aim to make these essentials more accessible to lower-income individuals and families. However, when prices are artificially capped, the supply of the product may decrease because producers might find it unprofitable to sell at lower prices. This can create shortages in the market, where the quantity demanded exceeds the quantity supplied. When demand outstrips supply, consumers may face rationing, long queues, or reduced product quality. Additionally, prolonged price ceilings can lead to a black market where goods are sold illegally at higher prices, circumventing the price controls.

What is a price floor?

A price floor is a government-imposed limit on how low a price can be charged for a product. It is typically set above the market equilibrium price to ensure that the price remains at a certain level, which can help protect producers' incomes by preventing prices from falling too low. This is common in markets such as agriculture, where the government may establish a price floor to ensure farmers can cover their production costs. While price floors can help stabilize incomes for producers, they can also lead to surpluses. When prices are artificially low, the quantity supplied exceeds the quantity demanded, resulting in excess supply that may necessitate government intervention, such as purchasing surplus goods. Additionally, a price floor can diminish consumer welfare as it leads to higher prices, limiting accessibility for some consumers.

Distinguish between a shift and movement along the demand/supply curves.

Movement along the demand curve = caused by a change in the good's own price.

Shift of the demand curve = caused by a change in a non-price factor (right = increase in demand, left = decrease).

Define market clearing.

Market clearing refers to when the forces of supply and demand work to meet at equilibrium in times of disequilibrium.

If price is above equilibrium → surplus → price falls to clear the surplus.

If price is below equilibrium → shortage → price rises as buyers compete for the scarce good.

Define market failure.

Market failure occurs when the allocation of goods and services by a free market is not efficient. This phenomenon signifies a situation where the market, left on its own, fails to allocate resources in a way that maximises the overall benefit to society.

Market failure justifies government intervention to correct inefficiencies and promote a more equitable distribution of resources. Governments can implement policies such as regulations, taxes, subsidies, or public provision of goods in response to market failures, aiming to enhance overall welfare.

How can market failures arise?

Externalities: These are costs or benefits that affect third parties not directly involved in a transaction. For example, pollution from a factory can harm the health of nearby residents, representing a negative externality. Conversely, a positive externality, such as a well-maintained garden, can enhance the value of surrounding properties.

Merit Goods: These are goods or services that the government believes are beneficial to society, but they may not be produced in adequate quantities because the market is too small, and there is little or no incentive for private production. Merit goods and services are those which individuals undervalue and the government’s preference for these goods and services, results in the subsidisation of their production or production through government agencies.

Public Goods: These are goods that are non-excludable and non-rivalrous, meaning that it's difficult to prevent anyone from using them, and one person's use does not diminish another's ability to use them. Examples include national defense, public parks, and street lighting. Because individuals can benefit from these goods without paying for them, private markets may underproduce them.

Monopoly Power: When a single firm dominates a market, it can manipulate prices and output levels to maximize profits at the expense of consumer welfare. This lack of competition can lead to higher prices and less innovation.

Information Asymmetry: This occurs when one party in a transaction has more or better information than the other. For example, a seller of a used car may have more knowledge about the car's condition than the buyer, potentially leading to adverse selection and market inefficiencies.

Inequity: While a market may be efficient, it can lead to unequal distributions of wealth and resources. If wealth is concentrated in the hands of a few, it can create social unrest and weaken overall demand.

Define price elasticity of demand.

Price Elasticity of Demand (PED) measures the magnitude of the responsiveness of quantity demanded of a good to a change in its price. It is defined as the percentage change in quantity demanded divided by the percentage change in price.

Formula:

$$\text{PED}=\frac{\%\ \Delta\ \text{Quantity Demanded}}{\%\ \Delta\ \text{Price}}$$

Due to the inverse relationship, the calculated value is always negative. By convention, PED is often reported as an absolute value.

Total Outlay (Total Revenue) Method — the calculation method required by the syllabus:

• Total Outlay = Price × Quantity

• If price rises and total outlay falls → demand is elastic.

• If price rises and total outlay rises → demand is inelastic.

• If price changes and total outlay stays the same → demand is unit elastic.

• (Same logic applies in reverse for a price fall.)

What are the implications for different values of Price Elasticity of Demand?

• PED = 0 (Perfectly Inelastic): Quantity demanded does not change at all when price changes. The demand curve is vertical. Implication: A price increase raises total revenue (TR = Price × Quantity) proportionally, as quantity sold remains unchanged. Example: life-saving medication.

• 0 < PED < 1 (Inelastic): Quantity demanded changes by a smaller percentage than price. Implication: An increase in price leads to a smaller decrease in quantity, so total revenue increases. A decrease in price leads to a smaller increase in quantity, so total revenue decreases. Example: essential goods like petrol or basic food.

• PED = 1 (Unit Elastic): Quantity demanded changes by exactly the same percentage as price. Implication: A change in price leaves total revenue unchanged. The revenue gain from a higher price is exactly offset by the revenue loss from lower sales, and vice versa.

• PED > 1 (Elastic): Quantity demanded changes by a larger percentage than price. Implication: An increase in price leads to a larger decrease in quantity, so total revenue decreases. A decrease in price leads to a larger increase in quantity, so total revenue increases. Example: luxury goods or goods with many close substitutes.

• PED = ∞ (Perfectly Elastic): Quantity demanded is extremely responsive to any price change. At a given price, any quantity can be sold, but any price increase results in quantity demanded falling to zero. The demand curve is horizontal. Implication: The firm is a price taker with no pricing power. Example: a homogeneous product in a perfectly competitive market.

List the factors affecting elasticity of demand.

Necessities and Luxuries

Goods and services which are classed as necessities such as bread, milk, sugar and flour tend to have a relatively inelastic demand, whereas goods classed as luxuries such as new cars, holidays, furniture, TVs and DVD players tend to have a relatively elastic demand.

Existence of Close Substitutes

Goods for which close substitutes exist (e.g. different brands of cars) tend to have a relatively more elastic demand than goods for which there are few if any close substitutes (e.g. electricity). The cross elasticity of demand co-efficient tends to be positive for substitute goods and negative for complementary goods.

$$\% \ \Delta Q_d \text{ of A} \, / \, \% \ \Delta P \text{ of B}$$

Complementary Goods

Goods used in conjunction with each other in consumption such as cars and petrol tend to have relatively inelastic demand. A rise in the price of petrol is not likely to be followed by a larger proportionate fall in the demand for petrol.

Proportion of Income Spent on the Good

If the proportion of a consumer’s income spent in consuming a good is relatively small, the demand for that good will tend to be relatively inelastic (think matches or milk). Vice versa, if the proportion spent on the good is relatively large, such as the consumption, a rise in the price or a fall in the price may be accompanied by a larger proportionate change in demand, making demand relatively price elastic for these types of goods and services.

The Length of Time Since a Price Change

The elasticity of demand can also be influenced by the amount of time that has elapsed since the price of a good or service has changed. In general terms the greater the lapse of time, the higher is the elasticity of demand because consumers will adjust their demand according to the development of substitute goods and services.

Identify and outline the different market/competition structures.

Perfect Competition

Perfect, pure or atomistic competition is a market structure characterised by a large number of sellers of a homogeneous (identical) product who have little to no influence over price or output and there is free or unrestricted entry into the industry.

Monopolistic competition

Monopolistic competition is usually characterised by a relatively large number of firms, usually small in scale and having a small influence over price because of their small market share.

Entry into the market and exit out of the market is relatively easy. Small scale firms with low capital requirements mean that barriers to entering the industry are minimal.

Firms produce and market a slightly differentiated product from their rivals. Products may be physically similar but differentiated by brand names, packaging, after sales service or locational convenience. Examples include small retail shops in shopping centres or malls.

Oligopoly

Oligopoly is a market structure characterised by a few large firms, usually between three and eight, who dominate the market in terms of their output, market share and employment. Firms sell a slightly differentiated product, and there are usually large restrictions on entry into the market such as the level of capital required to set up and carry out production.

Monopoly

Monopoly is a market situation in which there is only one seller or producer of a good or service. Although substitutes may exist for the monopolist’s product, they are not close substitutes and so the monopoly firm represents industry supply for that product.

What are the factors that affect demand for labour?

Output of a Firm

This factor relates directly to derived demand.

• Positive Relationship: An increase in consumer demand for a firm's product raises its output. To produce more, the firm typically needs more labour, shifting the labour demand curve to the right. A decrease in product demand reduces output and shifts labour demand to the left.

• Elasticity: The responsiveness of labour demand to changes in product demand depends on the price elasticity of demand for the final product. If product demand is elastic, a small change in price (caused by a change in wage costs) will lead to a large change in quantity demanded of the product, and thus a large change in labour demand.

Productivity of Labour

Productivity refers to the amount of output produced per worker (or per hour worked). An increase in labour productivity shifts the labour demand curve to the right.

• Causes of Increased Productivity:

  • Better Capital: More or better machinery and technology allow workers to produce more.

  • Improved Human Capital: Education, training, and skills development enhance worker efficiency.

  • Technological Advancements: Innovations in production processes or information technology.

  • Improved Management: More efficient organisation of work and production.

Cost of Other Inputs

This factor concerns the substitutability and complementarity of labour with other factors of production (capital, land, raw materials).

• Substitution Effect (Competing Inputs): If the price of capital (e.g., machinery) falls, a firm may substitute capital for labour. This reduces the demand for labour, shifting the labour demand curve to the left. Conversely, a rise in the price of capital could increase the demand for labour as firms switch to more labour-intensive methods.

• Complementarity Effect (Joint Inputs): If labour and capital are complements, a fall in the price of capital can increase the demand for labour. For example, cheaper computers may lead a firm to hire more data entry workers. The reduced cost of capital expands output, increasing the demand for all inputs, including labour. The net effect on labour demand depends on which effect (substitution or complement) is stronger.

What are the factors that affect supply of labour?

Pay and Remuneration

This is the most direct price signal affecting labour supply, encompassing not just the base wage but the entire compensation package.

• Level of Wages: An increase in the wage rate in a specific occupation or industry generally attracts a higher quantity of labour supplied. This can draw workers from other industries, reduce voluntary unemployment, and encourage non-participants (such as carers or early retirees) to enter the labour force.

• Non-Wage Remuneration: The total effective pay package includes fringe benefits such as superannuation contributions, health insurance, bonuses, company vehicles, and leave entitlements. Generous on-costs can make a position more attractive, effectively shifting the labour supply curve for that industry to the right without a change in the base nominal wage.

Working Conditions
This factor encapsulates the non-pecuniary attributes of a job. The perceived quality of a job influences labour supply independently of pay.

• Positives: Attributes like flexible working hours (including work-from-home potential), job security, generous leave provisions, autonomy, and a safe, pleasant physical environment increase the attractiveness of a job. Improvements in these conditions shift the supply curve to the right.

• Negatives: Dangerous, stressful, or dirty working conditions, unsociable hours, poor job security (casualisation), and a toxic workplace culture reduce the attractiveness of a job. To attract labour, such jobs may require a compensating wage differential, a higher pay rate to offset the negative utility. A deterioration in perceived working conditions shifts the supply curve to the left.

Human Capital (Skills, Experience, Education and Training)
Human capital represents the stock of competencies, knowledge, and personality attributes embodied in the ability to perform labour so as to produce economic value. It is a critical determinant of the quality and type of labour supplied.

• Acquisition: Human capital is developed through formal education, vocational training, and on-the-job experience. Investment in these activities increases a worker's future productive capacity.

• Impact on Supply: The supply of labour to occupations requiring high levels of specific human capital (e.g., neurosurgeons, software engineers) is relatively inelastic in the short run. The time and cost involved in acquiring these skills create a significant barrier to entry. An increase in the number of individuals obtaining a particular qualification will increase the supply of labour to that specific professional segment over time. Policy interventions, such as subsidised training places, aim to shift the supply curve for skilled labour to the right.

Occupational and Geographic Mobility of Labour
This refers to the ease with which workers can move between jobs (occupational mobility) and between locations (geographic mobility) in response to wage differentials and job availability. High immobility is a key cause of structural unemployment.

• Occupational Mobility:

  • Barriers include a lack of transferable skills, stringent professional licencing requirements, a psychological attachment to a vocation, and a lack of information about opportunities in other sectors.

  • Higher occupational mobility results in a more elastic aggregate labour supply, as workers can more easily shift into expanding industries.

• Geographic Mobility:

  • Barriers include significant costs of relocation (e.g., housing transaction costs like stamp duty), strong family and community ties, a partner's local employment, and a lack of information about distant job markets.

  • Lower geographic mobility creates pockets of labour shortages in some regions alongside pockets of high unemployment in others. Policies like relocation subsidies aim to reduce these barriers and increase the effective supply of labour to specific areas.

Participation Rate

The labour force participation rate is the proportion of the working-age population (typically defined as persons aged 15 years and over) that is either employed or actively seeking employment. It is a macro-level measure of labour supply.

• Calculation: Labour Force Participation Rate = (Labour Force / Working-Age Population) × 100.

• Influencing Factors: This rate is affected by social, cultural, and institutional factors. Trends such as the rising participation of women (driven by reduced gender discrimination, the growth of the service sector, and the availability of part-time work), the ageing population (reducing aggregate participation), and changing school retention rates all shift the aggregate supply of labour. The participation rate is a primary driver of long-run economic growth.