chapter 6

Government Actions in Markets

Introduction

This chapter explores how government interventions such as rent ceilings, minimum wage laws, taxes, production quotas, subsidies, and regulations on illegal goods affect market outcomes, efficiency, and fairness. Understanding these concepts is essential for analyzing real-world market policies and their consequences.

Rent Ceilings in the Housing Market

Price Ceilings and Rent Ceilings

• Price ceiling (or price cap): A regulation that makes it illegal to charge a price higher than a specified level.

• Rent ceiling: A price ceiling applied to the housing market.

• If the rent ceiling is set above equilibrium rent, it has no effect; if set below, it creates a housing shortage.

Effects of Rent Ceilings

• Housing shortage: Quantity of housing demanded exceeds quantity supplied.

• Increased search activity: Time spent searching for housing increases, raising opportunity costs.

• Illegal trading: Renters and landlords may engage in transactions above the legal ceiling.

Efficiency and Fairness of Rent Ceilings

• Rent ceilings set below equilibrium lead to deadweight loss and underproduction of housing services.

• Consumer and producer surplus shrink; increased search activity adds to inefficiency.

• Allocation methods (lottery, first-come-first-served, discrimination) do not guarantee fairness.

Key Terms and Formulas

• Deadweight loss: The loss of total surplus due to inefficient market outcomes.

• Marginal social benefit vs. marginal social cost: Inefficiency arises when benefit exceeds cost.

Minimum Wage in the Labour Market

Price Floors and Minimum Wage

• Price floor: A regulation that makes it illegal to trade at a price lower than a specified level.

• Minimum wage: A price floor applied to labour markets.

• If set above equilibrium wage, it creates unemployment; if below, it has no effect.

Effects of Minimum Wage

• Unemployment: Quantity of labour supplied exceeds quantity demanded.

• Legal wage rate cannot eliminate surplus; unemployment results.

• Minimum wage laws may increase unemployment among low-skilled, younger workers.

Efficiency and Fairness of Minimum Wage

• Leads to inefficient outcomes: employed quantity is less than efficient quantity.

• Supply of labour = marginal social cost (leisure forgone); demand for labour = marginal social benefit (value of goods produced).

• Deadweight loss and reduced worker/producer surplus.

Taxes and Market Outcomes

Tax Incidence

• Tax incidence: The division of the burden of a tax between buyers and sellers.

• If market price rises by the full tax, buyers pay; if less, both share; if not at all, sellers pay.

Equivalence of Tax on Buyers and Sellers

• Imposing a tax on either buyers or sellers has the same effect on market price and quantity.

Tax as a Wedge

• A tax creates a wedge between the price buyers pay and the price sellers receive.

• Equilibrium quantity is where the vertical gap between demand and supply equals the tax size.

Taxes and Efficiency

• Except for perfectly inelastic demand or supply, taxes create inefficiency and deadweight loss.

• Tax revenue is part of total surplus; decreased quantity creates deadweight loss.

Elasticity and Tax Incidence

• Division of tax depends on elasticities of demand and supply.

• Perfectly inelastic demand: buyers pay entire tax.

• Perfectly elastic demand: sellers pay entire tax.

• Perfectly inelastic supply: sellers pay entire tax.

• Perfectly elastic supply: buyers pay entire tax.

Examples of Tax Incidence

• Goods with inelastic demand (alcohol, tobacco, gasoline): buyers pay most of the tax.

• Labour (low elasticity of supply): sellers (workers) pay most of income and social security taxes.

Fairness in Taxation

• Benefits principle: People should pay taxes equal to the benefits they receive from government services.

• Ability-to-pay principle: People should pay taxes according to how easily they can bear the burden.

Production Quotas and Subsidies

Production Quotas

• Production quota: An upper limit to the quantity of a good that may be produced during a specified period.

• Quotas decrease quantity produced, raise price, and create inefficiency and incentives to cheat.

Subsidies

• Subsidy: A payment made by the government to a producer.

• Subsidies increase supply, lower market price, raise quantity produced, and can lead to overproduction and inefficiency.

Markets for Illegal Goods

Market Functioning

• Illegal goods (e.g., drugs) are prohibited, but markets still exist.

• Penalties on sellers decrease supply; penalties on buyers decrease demand.

• Penalties on both sides decrease both supply and demand, lowering quantity and affecting prices.

• Legalizing and taxing an illegal good can achieve similar outcomes to prohibition, but with different social implications.

Key Tables

Tax Incidence and Elasticity

Elasticity	Who Pays the Tax?
Perfectly Inelastic Demand	Buyer pays entire tax
Perfectly Elastic Demand	Seller pays entire tax
Perfectly Inelastic Supply	Seller pays entire tax
Perfectly Elastic Supply	Buyer pays entire tax

Key Formulas

• Deadweight Loss: $DWL = \frac{1}{2} \times (Q^* - Q_t) \times (P_t - P^*)$

• Tax Revenue: $TR = \text{Tax} \times Q_t$

• Consumer Surplus: $CS = \int_{0}^{Q^*} D(q) dq - P^* Q^*$

• Producer Surplus: $PS = P^* Q^* - \int_{0}^{Q^*} S(q) dq$

Summary Table: Effects of Government Actions

Policy	Market Effect	Efficiency	Fairness
Rent Ceiling	Shortage, illegal trading, increased search	Inefficient (deadweight loss)	Unfair (allocation issues)
Minimum Wage	Unemployment, surplus of labour	Inefficient (deadweight loss)	Debated (may not benefit poor)
Tax	Reduced quantity, price wedge	Inefficient (deadweight loss)	Depends on principle applied
Quota	Reduced quantity, higher price	Inefficient (underproduction)	May benefit producers
Subsidy	Increased quantity, lower price	Inefficient (overproduction)	May benefit producers
Illegal Goods Regulation	Reduced quantity, higher price, risk	Inefficient (social costs)	Complex (legal/social issues)

Conclusion

• Government interventions in markets can have significant effects on prices, quantities, efficiency, and fairness. Understanding the mechanisms and consequences of these policies is crucial for evaluating their impact on society and the economy.