Notes on Pollution, Externalities, and Education Economics (Ch. 16–17)
Chapter 16: Pollution, the Environment, and Global Warming
After studying this chapter, you should be able to:
- Describe the benefits and costs of pollution
- Model the externalities associated with pollution
- Describe the policy responses to pollution
- Assess methods to address pollution problems
Background and motivation
- Rising international awareness of climate change has increased concern about pollution and the environment.
- Environmentally friendly products and sustainable living have become common discussion points; government programs (e.g., green jobs) are promoted to stimulate growth.
- Even everyday activities generate pollution; e.g., burning fossil fuels emits greenhouse gases such as carbon dioxide.
What is pollution?
- Pollution is contamination of the environment that causes instability, harm, or disruption to ecosystems.
- It can be naturally occurring or anthropogenic (human-induced), but emphasis in policy is on human-induced pollution.
- The IPCC has concluded that most of the observed rise in temperatures since the 1950s is very likely due to anthropogenic causes.
The cost-benefit approach to environmental preservation
- Use the marginal benefit – marginal cost framework to evaluate pollution and regulations.
- The goal is not zero pollution, but an optimal level of pollution that maximizes net social welfare.
- Benefits of pollution (MB) can be large due to electricity generation, transport, communication, technology, and quality of life improvements.
- Costs of pollution (MC) include health impacts, climate change, habitat disruption, environmental degradation, and property value changes.
- The MB curve for electricity is downward-sloping due to diminishing marginal benefits; initial units of electricity (e.g., lighting homes) have high MB, while later uses have lower MB.
- The MC curve for electricity shows higher marginal costs as production scales up, reflecting the law of increasing marginal costs due to resource constraints and technology limits.
- The optimal level of production is where MB = MC, denoted Q, with the corresponding price P.
- MB and MC are market concepts for private decisions, but pollution externalities create market failures and social costs that differ from private costs.
Benefits of pollution (in economics terms)
- Benefits arise from activities that generate pollution indirectly through modern life: faster transport, communication, trade, electricity generation, etc.
- Willingness to pay (WTP) for an additional unit of electricity allows us to translate MB into dollars and compare with costs.
- Example: Opening a power plant first serves high-WTP customers (homes/businesses), yielding high MB initially; subsequent units (streetlights, refrigeration, etc.) have lower MB but still contribute to welfare.
- MB is the additional benefit from one more unit of a good; WB = willingness to pay for that unit.
Costs of pollution
- Private costs of production include input costs (coal, hydro, fuel, labor) and operational costs.
- Social costs include private costs plus negative externalities borne by third parties (health effects, climate effects, property values, ecosystem damage).
- The marginal cost (MC) curve typically shows private MC; social MC (MC_social) adds the external costs.
- Difference between MCsocial and MCprivate represents the negative externality.
The presence of externalities
- Externalities occur when costs or benefits of a trade spill over to third parties.
- Negative externalities: costs borne by others (health costs, reduced property values, climate impact).
- Positive externalities: benefits to third parties (e.g., education spillovers, pest control, knowledge spillovers).
- Examples of negative externalities beyond pollution: noise, traffic, unsightly yards, barking dogs.
Social costs vs private costs (illustration)
- Private marginal costs (MC_private) reflect costs borne by producers.
- Social marginal costs (MCsocial) = MCprivate + Negative Externality.
- A supply curve that reflects social costs shifts upward relative to the private supply curve.
- The more scarce the absorptive capacity of the environment, the larger the externality at higher production levels.
The optimal level of pollution in a market with negative externalities
- Without externalities, market equilibrium would be at MB = MC_private.
- With negative externalities, the socially optimal level of production is where MB = MC_social.
- If producers ignore externalities, the market produces too much pollution (quantity above socially optimal Q_social).
- The socially optimal quantity is where MB = MC_social.
Approaches to environmental preservation
- When negative externalities exist, society faces a trade-off: improving the environment comes with costs.
- Two broad policy approaches: command-and-control policies and property-rights-based policies (markets for rights).
Command-and-control (CAC) approaches
- Taxes and Fees: Pigovian taxes set at the size of the negative externality align private marginal cost with social marginal cost, shifting the supply curve upward to reflect the external cost.
- Example: Pollution tax on fuels (e.g., gasoline taxes) and carbon taxes (country-specific implementations such as Sweden’s carbon tax on fuels; U.S. gas taxes; etc.).
- In a simple diagram, a tax shifts the private MC to MC_social and reduces quantity toward the socially optimal level.
- Typical real-world examples: U.S. gasoline taxes, carbon taxes in various jurisdictions (e.g., Sweden, British Columbia).
- Emissions Limits (Quotas): Bans or caps on emissions impose a ceiling on pollution and require firms to reduce or offset emissions to stay within the limit.
- Example: DDT ban after ecological and health concerns; emissions limits on electric plants; cap on SO2 under Acid Rain Program in the U.S.
- If the limit is set at the socially optimal level, production at that level adheres to social welfare, but if the limit is too tight, it foregoes net benefits.
- Cap-and-trade and tradable rights: A cap on total emissions is set; rights to pollute are allocated or auctioned; firms can trade rights to emit to achieve reductions at low-cost.
- DDT case study: debates over malaria control using DDT versus ecological and health concerns; limits on DDT usage; related policy decisions.
Cap-and-trade, tradable rights, and carbon offsets
- Cap-and-trade: Establishes an emissions cap and distributes tradable emission permits. Emission reductions occur where cheapest; permits can be bought/sold.
- Tradable pollution rights: Permits to emit; reductions centralized to meet cap at low cost by allowing trading.
- Carbon offsets: Reductions in one location offset emissions elsewhere (e.g., wind farms, energy efficiency, reforestation). Used to meet emission targets where direct reductions are costly or infeasible.
- Kyoto Protocol: International agreement featuring emissions trading as a mechanism to reduce greenhouse gases. Cap-and-trade approaches are central to many climate policies.
- Acid Rain Program (U.S.): SO2 trading program under the Clean Air Act; permits traded on exchanges; substantial cost reductions in achieving targets.
- Chicago Climate Exchange: A market-based effort to trade carbon permits; price signals reflect demand for offsets/permits.
- Real-world takeaway: When markets assign property rights to pollute and allow trading, reductions can be achieved more cheaply than with uniform command-only restrictions.
Property rights and the Coase Theorem
- Ronald Coase argued that with well-defined property rights, private bargaining can achieve efficient outcomes in the presence of externalities, absent high negotiation costs.
- If the right to clean air is established, polluters can compensate those harmed by pollution; if the right to pollute is established, those harmed can compensate polluters to reduce emissions.
- Assignment of property rights can help internalize externalities and move toward the social optimum through bargaining.
Common property vs private property resources
- Common property resources: Resources that are collectively owned (air, public lands, many oceans, shared grazing land).
- Private property resources: Resources owned by individuals or firms; incentives to maintain and conserve differ due to ownership structure.
- The Tragedy of the Commons (Garrett Hardin, 1968): Collective ownership can lead to overuse and destruction as individuals pursue private gains while bearing only a fraction of the costs.
- Solutions to the tragedy of the commons include moving toward private property or creating transferable rights that allocate a shared resource efficiently.
- Fisheries example: ITQ (individual transferable quotas) allocate a share of total allowable catch to harvesters; ITQ-managed fisheries tend to have fewer stock collapses than non-ITQ ones.
- The Deadliest Catch: Reflects shift from fishing derby (race to fish) to ITQ-based management and its effects on smaller fishers.
Tradable pollution rights and real-world programs
- Kyoto Protocol and cap-and-trade frameworks assign tradable rights to emit pollutants; allows reductions where cheapest.
- U.S. experience with Acid Rain Program demonstrates large cost reductions from trading permits rather than enforcing per-polluter limits.
- Carbon offsets and carbon markets: Markets for offsets exist but can be fragile when regulatory demand is weak; price signals can fluctuate significantly.
Summary: Key concepts to remember
- Pollution, Negative externalities, Positive externalities
- Private marginal costs vs Social marginal costs
- Command-and-control vs Rights-based approaches
- Emissions taxes, Emissions limits, Cap-and-trade, Tradable rights, Carbon offsets
- Common property vs private property, Tragedy of the Commons
- ITQ, Deadliest Catch, Kyoto Protocol, Acid Rain Program, Chicago Climate Exchange
Think for yourself prompts (selected examples)
- What are some typical negative externalities from cell phone use? From fossil fuels? How do externalities relate to technology adoption and urban policy?
- How do tradable pollution rights compare to uniform emission caps in terms of cost and adaptability?
- Why might moral suasion be insufficient on its own to address widespread pollution? What combination of policies could be more effective?
Discussion Questions and Problems (selected items)
- The accompanying table shows MB and MC for paper production; answer: (a) equilibrium price; (b) equilibrium quantity; (c) identify negative externalities; (d) social vs private optimum; (e) socially optimal price/quantity given externalities; (f) steps to move from market to social optimum.
- If two power-plant smokestacks have different marginal costs of emission reduction, what is the cheapest way to reduce total emissions by a given amount? Compare per-stack reductions vs reallocating across stacks.
- Explain the difference between private and social marginal costs in the context of pollution and provide a numerical example.
- Discuss the Tragedy of the Commons with the example of common grazing land and explain how ITQs or similar rights could alter incentives.
- Describe cap-and-trade vs emission taxes; under what circumstances might one be preferred to the other? Provide a simple example.
Chapter 17: The Economics of Education
After studying this chapter, you should be able to:
- Describe the level and changes in educational attainment over time
- Describe the costs and benefits of education
- Define human capital
- Model the positive externalities associated with education
- Evaluate why some education is publicly provided
- Describe some of the issues surrounding education reform
Education in the United States: trends in attainment
- 1948: about one in three people over 25 had completed high school; about one in 20 had four or more years of college.
- 2008: almost a third of those over age 25 had four or more years of college; only 13% had not completed high school.
- The shift reflects rising demand for higher education and lower relative demand for low-education jobs.
- Table 17.1 (data excerpts, persons 25+):
- Not a high school graduate: 65.9% (1948) → 13.4% (2008)
- High school graduate: 20.5% (1948) → 31.2% (2008)
- Some college: 6.7% (1948) → 26.0% (2008)
- 4 or more years college: 5.4% (1948) → 29.4% (2008)
- Reasons for change: higher perceived value of education, lower opportunity costs, increased human capital demand.
The costs and benefits of education
- Use the marginal cost – marginal benefit framework to determine the optimal level of education for an individual.
- Costs of education:
- Opportunity costs: foregone earnings while in school; higher for post-secondary education.
- Direct costs: tuition, fees, books, supplies.
- Public vs private costs: K-12 is largely publicly provided; post-secondary costs include tuition and foregone earnings.
- Table 17.2 (costs of college attendance, 2011-2012):
- Public two-year: Tuition & Fees $2,963; Books & Supplies $1,182; Foregone Earnings $48,332; Total $52,477 per year
- Public four-year: Tuition & Fees $8,224; Books & Supplies $1,168; Foregone Earnings $48,332; Total $57,724 per year
- Private four-year: Tuition & Fees $28,500; Books & Supplies $1,213; Foregone Earnings $58,685; Total $88,398 per year
- Foregone earnings are the largest cost for many students; private vs public costs vary by sector.
- Martina/ The marginal costs of education (MC) rise with higher levels of education due to higher direct costs and larger foregone earnings (e.g., years 3-4 of college have higher costs than years 1-2).
The benefits of education (human capital and beyond)
- Human capital: acquired skills and knowledge that make a person more productive; higher productivity raises demand for skilled workers and their wages.
- Earnings and unemployment: higher education generally correlates with higher earnings and lower unemployment rates.
- Figure 17.2 (unemployment rates by education): less than high school > high school graduates > some college > bachelor’s or higher (in 2011 data); higher education associates with lower unemployment.
- Figure 17.3 (earnings by education level): median weekly earnings rise with education level; bachelor’s degree or higher > high school graduates > some college > less than high school.
- Non-monetary benefits: health outcomes, job satisfaction, retirement benefits, health insurance, and social benefits that accompany higher education levels.
- Children of more educated parents tend to have better early literacy and educational outcomes; intergenerational externalities exist.
- Positive externalities: education lowers crime, reduces welfare dependency, increases voter participation, and enhances social stability.
Why is education publicly provided?
- Positive externalities imply that private markets underprovide education relative to the social optimum.
- Public provision and subsidies (K-12 free public education, low-interest student loans, grants) raise the private benefit to a level closer to social benefit.
- Public funding for university education is smaller than for K-12 because the externalities are generally smaller for higher education.
Arthur Pigou and externalities
- Pigou introduced the idea of externalities and the concept of Pigouvian taxes/subsidies to correct market failures.
- Negative externalities: tax to move market toward social optimum (Pigouvian tax).
- Positive externalities: subsidy to move market toward social optimum.
Education spending and outcomes: evidence and debate
- Education spending per pupil has risen substantially in the U.S. over the past 50 years (adjusted to 2011 dollars): from about $3,000 in 1961 to nearly $12,000 in 2011 in public K-12 spending per student.
- Explanations for higher spending: smaller class sizes, higher integration of special needs, more administrators and support staff.
- However, increasing spending does not uniformly translate to better student performance.
- NAEP reading scores have been roughly flat since the 1970s despite higher spending; math trends show some improvements but not uniform across age groups.
- International comparisons (OECD): U.S. spends more per pupil than many developed countries, yet performance (e.g., NAEP, PISA) does not consistently outperform peers; graduation rates in the U.S. lag behind some other OECD countries.
Education reform: approaches and effectiveness
- School choice reforms: vouchers and charter schools aim to introduce competition and improve quality.
- Evidence on school choice is mixed; some studies show improvements in test scores; others show limited or inconsistent effects.
- Emphasis on teacher quality: selective entry into teaching, better training; pay reforms to attract higher-quality teachers; merit-based pay vs seniority-based pay.
The economics of education: MB and MC with externalities
- Positive externalities imply social MB exceeds private MB; thus individuals under-invest in education relative to the social optimum.
- Figure 17.6 shows MBprivate and MBsocial, with the positive externality represented as the vertical distance between MBsocial and MBprivate.
- The socially optimal level of education (Q*) is where MB_social = MC.
- Private market tends to deliver less education than is socially optimal, due to positive externalities.
Present and future values in education decisions (Appendix: Present Value and Future Value)
- The concept of present value (PV) and future value (FV) allows comparing costs now with benefits later.
- FV formula: where i is the interest rate and n is the number of periods.
- PV formula: PV = rac{FV}{(1+i)^n}
- Time preference: people value money now more than later; higher time preference reduces the present value of future earnings from education.
- The interest rate is a proxy for time preference.
- Factors influencing education investment decisions include: (a) earnings difference between careers with/without education, (b) investment costs (tuition, foregone earnings), (c) length of time to recoup costs, and (d) time preference.
Why is education investment important for policy?
- Because education has positive externalities, private markets fail to achieve the socially optimal level of education without intervention.
- Public policies (K-12 public provision, grants, student loans) attempt to raise the level of educational attainment toward the social optimum.
Key concepts to remember
- Human capital, Positive externalities, Negative externalities
- Private marginal costs, Social marginal costs
- Public provision and subsidies, School choice, Teacher pay reform
- Present value, Time preference, Future value
Summary: Connections and policy implications
- Education increases productivity and earnings (human capital) but generates externalities.
- Public policy often intervenes to correct under-provision due to positive externalities.
- Not all spending translates into improved outcomes; reform efforts aim to improve efficiency and equity.
Think for yourself prompts (selected)
- Why might higher private returns not fully reflect social benefits of education? How should policy respond?
- What are the pros and cons of school choice (vouchers vs. charter schools) in improving outcomes?
- How does time preference influence decisions to invest in education, given the present-value framework?
Appendix: Present and Future Values (recap)
- Present value and future value concepts apply to education investment decisions as a way to compare present costs with anticipated future benefits.
- Practical takeaway: when the present value of future earnings exceeds the present cost of education (including tuition and foregone earnings), investment in education is more likely to occur.
KEY CONCEPTS (Chapter 16):
- Pollution, Negative externalities, Positive externalities, Private marginal costs, Social marginal costs, Command-and-control, Emissions limits, Cap-and-trade, Tradable pollution rights, Carbon offsets, Common property resources, Tragedy of the commons.
KEY CONCEPTS (Chapter 17):
- Human capital, Positive externalities, Negative externalities, Private marginal benefits, Social marginal benefits, Public provision, Time preference, Present value, Future value