Unit 5: Welfare Economics

Paper: Intermediate Microeconomics (ECODSC 251)

Welfare economics is the branch of economics that evaluates the well-being of individuals and society as a whole. It focuses on the optimal allocation of resources and how different economic states affect social desirability.

1. Nature of Welfare Economics
2. Pigouvian Welfare Criterion
3. Pareto Optimality Criterion
4. Kaldor-Hicks Compensation Criterion
5. Social Welfare Function

1. Nature of Welfare Economics

Welfare economics aims to determine the efficiency of economic activities and their impact on social welfare. Unlike positive economics, which describes "what is," welfare economics is normative, dealing with "what ought to be" through value judgments.

Key Objectives:

To establish criteria for comparing different economic states.
To identify conditions for social optimum or maximum social welfare.
To evaluate the impact of policy changes (e.g., taxes, subsidies) on society.

2. Pigouvian Welfare Criterion

Named after A.C. Pigou, this criterion is based on cardinal utility and interpersonal comparisons.

Pigou's Principle: Economic welfare is that part of social welfare that can be brought directly or indirectly into relation with the measuring rod of money.

Dual Conditions for Increasing Welfare:

An increase in national income, provided it does not lead to a less equal distribution.
A transfer of income from the rich to the poor, provided it does not diminish the size of the national income.

3. Pareto Optimality Criterion

Vilfredo Pareto introduced a criterion that avoids interpersonal comparisons of utility by using ordinal utility.

Pareto Improvement: A change that makes at least one person better off without making anyone else worse off.

Pareto Optimality: A state where it is impossible to make any one individual better off without making at least one individual worse off.

Conditions for Pareto Optimality:

Efficiency in Exchange: Marginal Rate of Substitution (MRS) must be equal for all consumers.
Efficiency in Production: Marginal Rate of Technical Substitution (MRTS) must be equal for all producers.
Efficiency in Product Mix: MRS in consumption must equal the Marginal Rate of Transformation (MRT) in production.

4. Kaldor-Hicks Compensation Criterion

This criterion attempts to evaluate changes where some people gain and others lose, moving beyond the strict requirements of Pareto.

The Principle:

An activity increases social welfare if the gainers could potentially compensate the losers and still remain better off than before. Note that the compensation does not actually have to be paid; it only needs to be possible.

Kaldor Criterion: Focuses on the ability of the gainers to compensate the losers.
Hicks Criterion: Focuses on the inability of the losers to bribe the gainers to cancel the change.

Exam Focus: Key Distinctions

Pareto vs. Kaldor-Hicks: Pareto requires no one to be hurt; Kaldor-Hicks allows losers if gains are large enough to theoretically compensate them.
Value Judgments: Welfare economics is essentially built on value judgments, especially when using the Social Welfare Function.
Externalities: Market failure occurs when Pareto conditions are not met, often due to externalities (social costs/benefits not reflected in market prices).