What You Need to Know About Resource Allocation
Resource allocation is the biggest single topic in your IGCSE Economics exam. It appears in almost every past paper. Master this, and you control a huge chunk of your final grade. The Cambridge IGCSE syllabus (0455) dedicates more content to this section than any other.
This topic covers how markets work, why prices change, how governments step in when markets fail, and why no real economy is purely market-based or purely planned. Every concept here links to real-world decisions: what gets produced, how it gets produced, and who gets it.
Here is exactly what you need to know, how the examiner tests it, and where students throw away marks.
The Role of Markets in Allocating Resources
What Is a Market?
A market is any arrangement where buyers and sellers come together to exchange goods, services, or resources. It does not have to be a physical place. Online platforms, auction houses, stock exchanges, and local shops are all markets.
How Markets Allocate Resources
Markets allocate scarce resources through the price mechanism. When consumers want more of a good, demand rises, price rises, and producers are signalled to supply more. When demand falls, prices drop, and resources shift elsewhere.
Three fundamental questions every economy must answer:
- What to produce? Determined by consumer demand. Firms produce goods consumers are willing to pay for.
- How to produce? Determined by competition. Firms choose the lowest-cost method to maximise profit.
- For whom to produce? Determined by ability and willingness to pay. Those with higher incomes get more goods.
Buyers and Sellers
Buyers (consumers) create demand. Sellers (producers) create supply. The interaction between the two determines the market price and quantity traded. Neither side acts alone. Both respond to price signals.
Demand
Definition and the Law of Demand
Demand is the quantity of a good or service that consumers are willing and able to buy at a given price over a given time period. Both conditions matter: willingness alone is not demand. You must also have the purchasing power.
The law of demand states: as price rises, quantity demanded falls, and as price falls, quantity demanded rises, ceteris paribus (all other things being equal).
Individual Demand vs Market Demand
Individual demand is one consumer's demand for a good. Market demand is the total of all individual demands at each price level. You get market demand by adding up every consumer's quantity demanded at each price horizontally across a demand schedule.
The Demand Curve
A demand curve slopes downward from left to right. Price sits on the vertical axis, quantity demanded on the horizontal axis. The downward slope reflects the inverse relationship between price and quantity demanded.
Movements Along vs Shifts of the Demand Curve
This is where students lose marks constantly. Know the difference cold.
| Type of Change | Cause | What Happens |
|---|---|---|
| Movement along | Change in the good's own price | Move up or down the existing curve |
| Shift of the curve | Change in a non-price factor | Entire curve moves left or right |
Conditions of Demand (Shift Factors)
These are the non-price factors that shift the entire demand curve:
- Income: Higher income increases demand for normal goods, decreases demand for inferior goods.
- Price of substitutes: If the price of Coca-Cola rises, demand for Pepsi increases (rightward shift).
- Price of complements: If the price of petrol rises, demand for large cars falls (leftward shift).
- Tastes and preferences: Fashion trends, advertising, and health concerns shift demand.
- Population size: A larger population increases market demand.
- Expectations: If consumers expect prices to rise, they buy more now (demand shifts right).
Supply
Definition and the Law of Supply
Supply is the quantity of a good or service that producers are willing and able to offer for sale at a given price over a given time period.
The law of supply: as price rises, quantity supplied rises, and as price falls, quantity supplied falls, ceteris paribus. Higher prices mean higher potential profit, so firms are motivated to produce more.
The Supply Curve
A supply curve slopes upward from left to right. Price on the vertical axis, quantity supplied on the horizontal axis. The upward slope reflects the direct (positive) relationship between price and quantity supplied.
Movements Along vs Shifts of the Supply Curve
Same logic as demand. A change in the good's own price causes a movement along the supply curve. A change in any other factor shifts the entire curve.
Conditions of Supply (Shift Factors)
- Costs of production: Higher wages, raw material costs, or rent shift supply left (less supplied at every price).
- Technology: Better technology reduces costs, shifting supply right.
- Taxes: An indirect tax increases costs, shifting supply left.
- Subsidies: A subsidy reduces costs, shifting supply right.
- Number of firms: More firms entering the market shifts supply right.
- Weather/natural conditions: Relevant for agricultural markets. Good weather shifts supply right.
Price Determination
Equilibrium Price and Quantity
The equilibrium price is where demand equals supply. At this price, the quantity consumers want to buy exactly matches the quantity producers want to sell. There is no tendency for the price to change.
Excess Demand and Excess Supply
| Situation | Price Relative to Equilibrium | What Happens |
|---|---|---|
| Excess demand (shortage) | Price is below equilibrium | Consumers compete for limited goods, price is bid up |
| Excess supply (surplus) | Price is above equilibrium | Firms cannot sell all output, price falls |
Worked Example
A demand schedule shows: at $2, quantity demanded is 100 units; at $4, quantity demanded is 60 units. A supply schedule shows: at $2, quantity supplied is 40 units; at $4, quantity supplied is 80 units.
At $2: demand (100) exceeds supply (40). Excess demand of 60 units. Price rises.
At $4: supply (80) exceeds demand (60). Excess supply of 20 units. Price falls.
Equilibrium lies between $2 and $4, where the two schedules intersect.
Price Changes
Prices change when demand or supply shifts. You must be able to explain and illustrate the effect of any shift on equilibrium price and quantity.
Quick Reference
| Change | Effect on Price | Effect on Quantity |
|---|---|---|
| Demand increases (shifts right) | Price rises | Quantity rises |
| Demand decreases (shifts left) | Price falls | Quantity falls |
| Supply increases (shifts right) | Price falls | Quantity rises |
| Supply decreases (shifts left) | Price rises | Quantity falls |
Price Elasticity of Demand (PED)
Definition and Formula
PED measures the responsiveness of quantity demanded to a change in price.
Formula: PED = % change in quantity demanded / % change in price
PED is always negative (because of the law of demand), but we typically use the absolute value.
Interpreting PED Values
| PED Value | Description | Example |
|---|---|---|
| Greater than 1 | Elastic: demand is responsive to price | Luxury goods, branded clothing |
| Less than 1 | Inelastic: demand is unresponsive to price | Necessities, petrol, salt |
| Equal to 1 | Unitary elastic | Rare in practice |
| Equal to 0 | Perfectly inelastic | Life-saving medication |
| Infinity | Perfectly elastic | Identical commodities in a competitive market |
Factors Affecting PED
- Availability of substitutes: More substitutes = more elastic.
- Necessity vs luxury: Necessities = inelastic. Luxuries = elastic.
- Proportion of income: Goods taking a large share of income = more elastic.
- Time period: Demand is more elastic over longer time periods (consumers can find alternatives).
- Habit/addiction: Addictive goods = inelastic.
PED and Total Revenue
This is a favourite IGCSE exam question. Know this relationship perfectly:
- If demand is elastic (PED > 1): a price cut increases total revenue. A price rise decreases total revenue.
- If demand is inelastic (PED < 1): a price cut decreases total revenue. A price rise increases total revenue.
Worked Example
A cinema raises ticket prices from $10 to $12. Attendance drops from 500 to 350 per week.
% change in quantity demanded = (350 - 500) / 500 x 100 = -30%
% change in price = (12 - 10) / 10 x 100 = +20%
PED = -30% / +20% = -1.5
The absolute value is 1.5. Demand is price elastic. The cinema should reconsider the price increase, because total revenue fell from $5,000 (500 x $10) to $4,200 (350 x $12).
Price Elasticity of Supply (PES)
Definition and Formula
PES measures the responsiveness of quantity supplied to a change in price.
Formula: PES = % change in quantity supplied / % change in price
PES is always positive (because of the law of supply).
Interpreting PES Values
- PES > 1: Elastic supply. Producers can easily increase output when price rises.
- PES < 1: Inelastic supply. Producers struggle to increase output quickly.
Factors Affecting PES
- Spare capacity: Firms with unused capacity can respond quickly (more elastic).
- Stock levels: If firms hold large stocks, supply is more elastic.
- Time period: Supply is more elastic over longer time periods.
- Mobility of factors of production: If labour and capital can be switched easily, supply is more elastic.
- Nature of the product: Agricultural goods are often inelastic in the short run (crops take time to grow). Manufactured goods are more elastic.
Market Economic System
How It Works
A market economy relies on the price mechanism to allocate resources. Private individuals and firms own the factors of production. Decisions about what, how, and for whom to produce are made through market forces of demand and supply.
Advantages
- Consumer sovereignty: production responds to consumer preferences.
- Efficient resource allocation through the price mechanism.
- Incentive to innovate and reduce costs (profit motive).
- Wide variety of goods and services.
- No need for a costly government planning bureaucracy.
Disadvantages
- Income inequality: those who cannot earn have limited access to goods.
- Public goods will not be provided (no profit incentive).
- Merit goods will be under-consumed (consumers may not recognise their full benefits).
- Demerit goods will be over-consumed.
- Externalities are ignored (market prices do not reflect social costs or benefits).
- Monopolies may develop, restricting output and raising prices.
Market Failure
Market failure occurs when the free market fails to allocate resources efficiently. The result is either too much or too little of a good being produced compared to the socially optimal level.
Causes of Market Failure
Externalities
Externalities are costs or benefits that affect third parties who are not involved in the transaction.
| Type | Definition | Example | Market Outcome |
|---|---|---|---|
| Negative externality of production | Cost imposed on third parties by producers | Factory pollution affecting nearby residents | Overproduction |
| Negative externality of consumption | Cost imposed on third parties by consumers | Passive smoking, traffic congestion | Overconsumption |
| Positive externality of production | Benefit to third parties from production | Research and development spillovers | Underproduction |
| Positive externality of consumption | Benefit to third parties from consumption | Vaccination, education | Underconsumption |
Public Goods
Public goods have two characteristics:
- Non-excludable: You cannot prevent anyone from using them, even if they do not pay.
- Non-rivalrous: One person's use does not reduce availability for others.
Examples: street lighting, national defence, public parks.
The free-rider problem means private firms will not provide public goods because they cannot charge for them. Government must step in.
Merit and Demerit Goods
- Merit goods (education, healthcare, vaccinations) provide greater benefits than consumers realise. The market under-provides them because people undervalue the long-term benefits. Government response: subsidies, free provision, legislation (compulsory schooling).
- Demerit goods (tobacco, alcohol, drugs) cause greater harm than consumers realise. The market over-provides them. Government response: taxes, bans, advertising restrictions, minimum age laws.
Information Failure
Consumers or producers may lack full information about a product. If a consumer does not know that a food product is unhealthy, they may over-consume it. Imperfect information distorts market outcomes.
Government Responses to Market Failure
- Indirect taxes: Placed on demerit goods to raise price and reduce consumption.
- Subsidies: Given for merit goods to lower price and encourage consumption.
- Legislation and regulation: Pollution limits, safety standards, minimum age restrictions.
- Direct provision: Government provides public goods and merit goods directly.
- Information provision: Health warnings, nutritional labelling.
Mixed Economic System
No real economy is purely market or purely planned. Every economy is a mixed economy, combining elements of both systems. The question is the degree of government involvement.
Features of a Mixed Economy
- Both private sector and public sector coexist.
- The price mechanism allocates most resources, but the government intervenes where markets fail.
- Government provides public goods, regulates externalities, and redistributes income.
- Private firms produce most goods and services for profit.
Why Mixed Economies Exist
Pure market economies produce inequality and fail to provide public goods. Pure planned economies suffer from inefficiency, lack of consumer choice, and poor incentives. The mixed economy attempts to get the benefits of both while limiting their weaknesses.
Common Mistakes to Avoid
| Mistake | Correction |
|---|---|
| Saying "demand increased" when price changes | A change in price causes a movement along the curve, not a shift. Say "quantity demanded increased." |
| Forgetting "willing and able" in definitions | Always include both words for demand and supply definitions. |
| Confusing elastic and inelastic | Elastic = responsive (PED > 1). Inelastic = unresponsive (PED < 1). |
| Not linking PED to total revenue | Always explain the revenue implication. Examiners reward this link. |
| Listing externalities without identifying the type | State whether it is production or consumption, and positive or negative. |
| Calling public goods "government goods" | Public goods are defined by non-excludability and non-rivalry, not by who provides them. |
Self-Check Questions
Test yourself on these IGCSE-style questions. Cover the answers and attempt each one before checking.
1. A good has a PED of 0.4. The firm raises its price by 10%. What happens to total revenue?
2. Explain why vaccination is considered a merit good.
3. A government places a tax on sugary drinks. Using demand and supply analysis, explain the effect on equilibrium price and quantity.
4. Give two reasons why supply of agricultural products tends to be price inelastic in the short run.
Final Revision Checklist
Use this before your IGCSE Economics exam. If you cannot explain each point from memory, revisit that section.
- Define a market and give three examples of different market types.
- State the law of demand and the law of supply.
- Distinguish between a movement along and a shift of a demand/supply curve.
- List at least four demand shift factors and four supply shift factors.
- Draw and explain equilibrium using a demand and supply diagram.
- Calculate PED given data and interpret the result.
- Explain the link between PED and total revenue for elastic and inelastic goods.
- List three factors affecting PED and three affecting PES.
- Define and give examples of public goods, merit goods, and demerit goods.
- Explain four types of externality with examples.
- Describe three government responses to market failure.
- Compare the strengths and weaknesses of market, planned, and mixed economies.
Complete revision notes on The Allocation of Resources for Cambridge IGCSE Economics (0455). Covers markets, demand, supply, price determination, elasticity (PED and PES), market failure, and economic systems with worked examples, common mistakes, and self-check questions.
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