Elasticities of Demand 2

Perfectly Elastic Demand vs Perfectly Inelastic Demand

The effect of things like government intervention and changes in income may have different impacts on a market if demand is perfectly elastic or perfectly inelastic.

Perfectly elastic demand

Perfectly elastic demand - PED = +/- infinity.
- Any price increase will cause demand to drop to zero.

Perfectly inelastic demand

Perfectly inelastic demand - PED = zero.
- Any price change won't affect demand.

'I' for inelastic!

A perfectly inelastic demand curve would look vertical on a diagram as the quantity demanded would be the same regardless of the price.
An easy way to remember this is that the more inelastic demand is, the more the demand curve looks like an 'i' for 'inelastic'.

What Affects the Elasticity of Demand?

There are a number of factors that affect the elasticity of demand.

Availability of substitute goods/services

The more substitutes there are available, the more price elastic a good is.
This is because it is easy to find an alternative product as a replacement if the price of one good rises.
- E.g. washing detergents are fairly price elastic. If the price of one goes up, you can easily swap it for an alternative.

Percentage of income and time

The higher the proportion of income spent, the more elastic the good or service is. People are more sensitive to the price of a TV vs a Mars bar.
Goods tend to be more price elastic in the long run because time can be devoted to searching for appropriate alternatives.

Type of good

The nature of the good can influence how elastic the demand is.
Addictive goods tend to be more price inelastic because a change in price is unlikely to affect quantity significantly (if users feel they have a need for the product).
- E.g. cigarettes.
But items that are not absolutely essential are more elastic.
- E.g. kitchen roll.

Impact of indirect taxes

The impact of an indirect tax depends on the PED of the good or service.
Picture a tax as effectively shifting supply to the left. This leads to a fall in demand.
However, if the good has inelastic demand, the reduction in consumption will be small. The consumer burden is significantly higher than the producer burden.
The reverse is true for an indirect tax on a good or service with elastic demand.
Therefore PED is central to the impact of an indirect tax.

Impact of subsidies

The impact of a subsidy depends on the PED of the good or service.
Effectively, a subsidy shifts the supply curve to the right. This means demand should increase.
If the good or service has an inelastic demand, the price will drop more than the quantity increases.
If the good or service has an elastic demand, the price will drop less than the quantity increases.
Therefore PED is central to the impact of a subsidy.

1Introduction to Markets

2Market Failure

2.1Market Failure

2.1.1Types of Market Failure

2.1.2Externalities

2.1.3The Deadweight Welfare Loss of Externalities

2.1.4A-A* (AO3/4) - The Externalities of Education

2.1.5Public Goods

2.1.6Information Gaps

2.1.7End of Topic Test - Market Failure

2.1.8Application Questions - Market Failure

2.2Government Intervention

2.2.1Government Intervention in Markets

2.2.2Subsidies & Price Controls

2.2.3Pollution Permits & Regulation

2.2.4A-A* (AO3/4) - European Emissions Trading

2.2.5State Provision & Information Provision

2.2.6Government Failure

2.2.7End of Topic Test - Government Intervention

2.2.8A-A* (AO3/4) - Government Intervention

3The UK Macroeconomy

3.1Measures of Economic Performance

3.1.1Measuring Economic Growth

3.1.2National Income Data

3.1.3Inflation

3.1.4Causes of Inflation

3.1.5Consequences of Inflation

3.1.6Employment & Unemployment

3.1.7Causes & Impact of Unemployment

3.1.8A-A* (AO3/4) - Hysteresis

3.1.9Balance of Payments

3.1.10Current Account Deficit & Imbalances

3.1.11End of Topic Test - Economic Performance

3.1.12Application Questions Macroeconomy

3.2Aggregate Demand

3.2.1Aggregate Demand

3.2.2Consumption

3.2.3Investment

3.2.4Government Expenditure

3.2.5Net Trade

3.2.6End of Topic Test - Aggregated Demand

3.2.7Application Questions - AD

3.3Aggregate Supply

3.3.1Aggregate Supply

3.3.2End of Topic Test - Aggregated Supply

3.3.3A-A* (AO3/4) -Aggregate Supply

3.4National Income

3.4.1National Income

3.4.2Injections & Withdrawals

3.4.3Equilibrium Level of Real National Output

3.4.4Multiplier Effect

3.4.5End of Topic Test - National Income

3.4.6Application Questions - National Income

3.5Economic Growth

3.5.1Causes of Economic Growth

3.5.2Output Gaps

3.5.3Business Cycle

3.5.4Impact of Economic Growth

3.5.5End of Topic Test - Economic Growth

3.5.6A-A* (AO3/4) - Growth

4The UK Economy - Policies

4.1Macroeconomic Objectives & Policies

4.1.1Possible Objectives

4.1.2Demand-Side Policies - Monetary

4.1.3Demand-Side Policies - Monetary 2

4.1.4A-A* (AO3/4) - The Future of Interest Rates

4.1.5Demand-Side Policies - Fiscal

4.1.6Demand-Side Policies in 2007-08

4.1.7Strengths & Weaknesses of Demand Side

4.1.8Supply-Side Policies

4.1.9Supply-Side Policies 2

4.1.10Conflicts Between Objectives

4.1.11A-A* (AO3/4) - Conflicting Incentives

4.1.12Phillips Curve

4.1.13End of Topic Topic - Policies & Objectives

4.1.14Application Questions - UK Policies

5Business Behaviour

5.1Business Growth

5.1.1Size & Types of Firms

5.1.2Business Growth

5.1.3Pros & Cons of External Expansion

5.1.4Demergers

5.1.5End of Topic Test - Business Growth

5.1.6A-A* (AO3/4) - Business Growth

5.2Business Objectives

5.2.1Business Objectives

5.2.2End of Topic Test - Business Objectives

5.2.3Application Questions - Business Objectives

5.3Revenues, Costs & Profits

5.3.1Revenue

5.3.2Costs

5.3.3Economies & Diseconomies of Scale

5.3.4Profits

5.3.5Profits 2

5.3.6End of Topic Test - Revenue, Costs & Profits

5.3.7A-A* (AO3/4) - Revenue, Costs & Profit

6Market Structures

6.1Market Structures

6.1.1Efficiency

6.1.2Perfect Competition

6.1.3Perfect Competition 2

6.1.4Monopolistic Competition

6.1.5Oligopolies

6.1.6The Prisoner's Dilemma

6.1.7Collusion in Oligopolistic Markets

6.1.8A-A* (AO3/4) - Which Factors Affect Collusion?

6.1.9Monopolies

6.1.10Price Discrimination

6.1.11Monopsony

6.1.12A-A* (AO3/4) - Models in Economics

6.1.13Contestability

6.1.14Benefits of Contestability

6.1.15End of Topic Test - Market Structures

6.1.16Application Questions - Market Structures

6.1.17A-A* (AO3/4) - Cereal Collusion

6.2Labour Market

6.2.1Demand for Labour

6.2.2Supply of Labour

6.2.3Labour Market Imperfections

6.2.4A-A* (AO3/4) - Labour Productivity & Unemployment

6.2.5A-A* (AO3/4) - What Level of Unionisation is Good?

6.2.6Wage Determination

6.2.7Elasticity of Labour Supply & Demand

6.2.8Intervention in Setting Wages

6.2.9End of Topic Test - Labour Market

6.2.10A-A* (AO3/4) - Labour Markets

6.3Government Intervention

6.3.1Reasons for Government Intervention

6.3.2Government Promotion of Competition

6.3.3Usefulness of Competition Policy & Examples

6.3.4A-A* (AO3/4) - Modern Competition Policy

6.3.5Privatisation

6.3.6Government Regulation

6.3.7A-A* (AO3/4) - Nationalisation vs Privatisation

6.3.8Government Protection of Suppliers and Employees

6.3.9Impact of Government Intervention

6.3.10End of Topic Test - Government Intervention

6.3.11Application Questions - Government Intervention

7A Global Perspective

8Finance & Inequality

8.1Poverty & Inequality

8.1.1Absolute & Relative Poverty

8.1.2Inequality

8.1.3Inequality 2

8.1.4Lorenz Curve

8.1.5Government Policy on Poverty

8.1.6End of Topic Test - Poverty & Inequality

8.1.7A-A* (AO3/4) - Inequality & Poverty

8.2Emerging & Developing Economies

8.2.1Measures of Development

8.2.2Factors Influencing Growth & Development

8.2.3Barriers to Development

8.2.4Barriers to Development 2

8.2.5A-A* (AO3/4) - The Bottom Billion

8.2.6Development Strategies

8.2.7Interventionist Strategies

8.2.8Aid

8.2.9International Institutions

8.2.10International Institutions 2

8.2.11End of Topic Test - Emerging & Developing

8.2.12Application Questions - Developing Countries

8.3The Financial Sector

8.3.1Role of Financial Markets

8.3.2Market Failure in the Financial Sector

8.3.3Role of Central Banks

8.3.4End of Topic Test - The Financial Sector

8.3.5A-A* (AO3/4) - Financial Sector

8.4Role of the State in the Macroeconomy

8.4.1Public Expenditure

8.4.2Taxation

8.4.3Public Sector Finances

8.4.4End of Topic Test - Role of the State

8.4.5Application Questions - Role of the State

9Examples of Global Policy

9.1International Policies

9.1.1Global Debt & Deficit Policies

9.1.2Poverty & Inequality Policies

9.1.3Changes in Interest Rates

9.1.4Competitiveness Policies

9.1.5End of Topic Test - International Policies

9.1.6A-A* (AO3/4) - International Policies

9.2Policy Responses to Shocks

9.2.1International Tax Policies

9.2.2Problems for Policymakers

9.2.3End of Topic Test - Policy Responses

9.2.4Application Questions - Policy Responses

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