Unit 5: Welfare Economics and Keynesian Economics - Subjective Questions

Welfare economics studies how economic resources can be allocated to improve individual and social well-being. In the neoclassical tradition, welfare is primarily analyzed through individual preferences, utility, and the efficient allocation of scarce resources.

Main features:

• Individuals are assumed to have preferences that can be represented by a utility function.
• Consumers maximize utility subject to income and price constraints.
• Firms maximize profit subject to technological constraints.
• Competitive equilibrium is considered efficient under suitable assumptions.
• The first fundamental theorem of welfare economics states that a competitive equilibrium is Pareto efficient, provided there are no externalities, public goods, or information failures.

However, Pareto efficiency does not necessarily imply an equitable distribution of income. Therefore, welfare economics distinguishes between efficiency and equity.

A consumer maximizes utility by choosing the combination of goods that provides the highest attainable satisfaction within the limits of income and prices.

The consumer's budget constraint is:

where and are the prices of goods and , and is income.

Equilibrium conditions:

• The consumer selects a point on the budget line.
• The highest possible indifference curve is reached.
• At an interior equilibrium, the slope of the indifference curve equals the slope of the budget line:

• Equivalently, the marginal utility per unit of expenditure is equalized:

This condition ensures that no reallocation of expenditure between goods can increase total utility.

A firm is assumed to maximize profit, which is the difference between total revenue and total cost:

For a price-taking firm, total revenue is , so profit is maximized when the additional revenue from selling one more unit equals the additional cost of producing it.

The first-order condition is:

Under perfect competition, the firm's marginal revenue equals the market price. Therefore:

Interpretation:

• If , increasing output raises profit.
• If , reducing output raises profit.
• Profit is maximized when , provided the marginal-cost curve is rising at the equilibrium point.

In the long run, free entry and exit may eliminate economic profit, resulting in as well as under perfect competition.

The hedonistic foundation of welfare economics is associated with the idea that economic welfare depends on pleasure, satisfaction, or utility. Individuals are viewed as seeking pleasure and avoiding pain.

Main assumptions:

• Utility represents the satisfaction obtained from consuming goods and services.
• Individuals are rational and seek to maximize utility.
• Utility can be used as a basis for evaluating economic states.
• Social welfare may be considered a function of individual utilities, such as:

• In early utilitarian thought, utilities were sometimes treated as measurable and comparable across individuals.

Limitations:

• Utility is subjective and cannot be directly observed.
• Interpersonal comparisons of utility are difficult.
• Human welfare includes non-material and social dimensions that may not be captured by utility.
• Maximizing aggregate utility may justify unequal distributions.
• Individual preferences may be shaped by poverty, social pressure, or incomplete information.

Thus, hedonism provides an important foundation but is insufficient as a complete theory of social welfare.

The cardinal and ordinal approaches differ in how they interpret utility.

Cardinal utility:

• Utility is assumed to be measurable in numerical units.
• Differences in utility are considered meaningful.
• It permits, at least in principle, interpersonal comparisons of utility.
• Early utilitarian welfare economics relied heavily on this approach.

Ordinal utility:

• Utility represents only the ranking of preferences.
• Numerical magnitudes have no independent meaning.
• A consumer can state that bundle is preferred to bundle , but cannot state that provides twice as much utility as .
• Modern neoclassical economics mainly uses ordinal utility.

Example: If a consumer ranks , the ordinal approach uses only this ranking. A cardinal approach would attach meaningful numerical values such as , , and .

The ordinal approach is less demanding and is closely connected with indifference-curve analysis, but it makes interpersonal welfare comparisons more difficult.

The fundamental theorems of welfare economics connect competitive markets with social efficiency.

First fundamental theorem:
Every competitive equilibrium is Pareto efficient, assuming:

• Perfect competition.
• Complete markets.
• No externalities.
• No public goods.
• Perfect information.

A situation is Pareto efficient when no individual can be made better off without making someone else worse off.

Second fundamental theorem:
Under suitable conditions, every Pareto-efficient allocation can be achieved as a competitive equilibrium after an appropriate redistribution of initial endowments.

This theorem separates two issues:

• Distribution: determined through redistribution of income or initial resources.
• Efficiency: achieved through competitive markets.

The theorem supports the idea that equity can be pursued through transfers while preserving market efficiency. In practice, however, lump-sum transfers are difficult to implement, and real economies often contain market failures.

Pareto efficiency is an important criterion in welfare economics, but it does not provide a complete judgment about social welfare.

An allocation is Pareto efficient if no person can be made better off without making another person worse off. It indicates that resources cannot be rearranged to improve at least one individual's position without harming someone else.

Relationship with welfare:

• A Pareto improvement increases the welfare of at least one person without reducing the welfare of anyone else.
• A Pareto-efficient allocation is considered economically efficient.
• Competitive equilibrium may generate Pareto efficiency under ideal conditions.

Limitations:

• Several Pareto-efficient allocations may exist.
• Pareto efficiency does not determine which distribution is fair.
• A highly unequal allocation can still be Pareto efficient.
• It cannot evaluate changes that benefit some people while harming others.

Therefore, welfare judgments require both efficiency criteria and an explicit ethical or social welfare function.

Piero Sraffa criticized the neoclassical theory of value and distribution, especially its reliance on the marginal productivity theory of distribution and the concept of capital as a single measurable factor.

Main points of the critique:

• Capital consists of heterogeneous goods such as machines, buildings, and inventories; these cannot always be reduced to one quantity of capital independently of prices.
• The value of capital goods depends on the distribution of income and relative prices.
• Measuring capital before knowing the rate of profit can involve circular reasoning.
• A change in the rate of profit can alter the chosen technique of production in complex ways.
• Capital reversal and reswitching show that a lower interest rate does not necessarily imply the use of a more capital-intensive technique.

Sraffa's approach emphasized the production of commodities by means of commodities and analyzed prices and distribution through a surplus framework. His critique challenged the idea that factor prices are automatically determined by the marginal products of independently measurable factors.

Capital reversal occurs when the relationship between the rate of profit and the capital intensity of production does not follow the simple neoclassical pattern. A technique that appears more capital-intensive at one rate of profit may not remain so at another rate.

Reswitching occurs when the same production technique becomes profitable at both a high and a low rate of profit, while another technique is preferred at an intermediate rate of profit.

Importance:

• Neoclassical theory often assumes an inverse relationship between the rate of interest and the capital-labor ratio.
• Reswitching shows that this relationship may not be monotonic.
• It challenges the claim that a lower interest rate necessarily induces firms to adopt more capital-intensive methods.
• It weakens the interpretation of the interest rate as a simple reward for waiting or abstinence.
• It questions the use of a single aggregate measure of capital in production functions.

Thus, Sraffa's analysis demonstrates that distribution and technique choice may be jointly determined by prices and income distribution.

Keynes developed his analysis in the context of the Great Depression, when economies experienced mass unemployment and unused productive capacity. He rejected the classical belief that flexible wages and prices automatically guarantee full employment.

Theoretical setting:

• The level of employment is determined by effective demand.
• Firms employ workers according to expected sales and expected profits.
• Aggregate demand consists mainly of consumption and investment expenditure:

• In a simple economy, equilibrium income is determined where planned expenditure equals output:

• Consumption generally rises with income, but less than proportionately.
• Investment is unstable because it depends on expectations, the marginal efficiency of capital, and the rate of interest.
• Unemployment can persist even when workers are willing to work at prevailing wages.

Keynes therefore emphasized demand management rather than automatic market adjustment.

The principle of effective demand states that the level of employment and national income is determined by the point at which aggregate demand equals aggregate supply.

Keynes represented this through the aggregate demand price and aggregate supply price. The equilibrium level of employment is reached where the two are equal.

In a simple model:

where is income, is consumption, and is investment.

Significance:

• Producers base employment decisions on expected demand for their output.
• If expected demand is low, firms reduce production and employment.
• The economy can settle at an equilibrium below full employment.
• Increased saving does not automatically lead to an equal increase in investment.
• Government expenditure can raise aggregate demand when private demand is inadequate.

Effective demand explains why involuntary unemployment can exist and why demand-management policies may be necessary.

Keynes proposed that consumption depends primarily on current income. The simplest consumption function is:

where is autonomous consumption and is the marginal propensity to consume, with .

In a simple economy without government and foreign trade:

Substituting the consumption function:

Therefore:

and:

The investment multiplier is:

Since , it can also be written as:

A rise in investment causes a more than proportionate rise in income because the initial expenditure becomes income for others, who spend part of it again.

Investment is a major determinant of income and employment in Keynesian economics. Unlike consumption, it is highly unstable and strongly influenced by expectations.

The marginal efficiency of capital (MEC) is the expected rate of return on an additional unit of capital. Investment is encouraged when the MEC exceeds the rate of interest.

The investment condition is:

where is the rate of interest.

Role of expectations:

• Firms estimate future revenues and costs.
• Optimistic expectations raise the MEC and stimulate investment.
• Pessimistic expectations reduce investment, even if interest rates are low.
• Uncertainty can cause firms to postpone investment.

A fall in investment reduces aggregate demand and income through the multiplier process. Since expectations can change suddenly, investment fluctuations may generate business cycles and prolonged unemployment.

Keynes explained the rate of interest as the reward for giving up liquidity. People prefer to hold wealth in money because money provides security and flexibility.

The demand for money has three motives:

• Transaction motive: money held for everyday purchases.
• Precautionary motive: money held for unexpected expenses.
• Speculative motive: money held to take advantage of changes in bond prices and interest rates.

The money-market equilibrium is:

where is the money supply and is liquidity preference, which rises with income and generally falls as the interest rate rises.

Implications:

• An increase in money supply can reduce the interest rate.
• A higher income level increases transaction and precautionary demand for money.
• At very low interest rates, people may expect rates to rise and bond prices to fall, so they hold money instead. This situation is called a liquidity trap.

The liquidity trap limits the effectiveness of monetary policy.

Keynes did not completely reject the marginal productivity theory of distribution, although he criticized several classical assumptions surrounding it. He accepted that, under appropriate conditions, the demand for a factor of production is related to its contribution to output.

Key aspects of Keynes's position:

• The marginal product of labor can influence the demand for labor.
• Firms compare the expected value of additional output with the wage cost.
• Employment is determined by the interaction between labor demand and effective demand.
• The marginal productivity principle is more applicable to the individual firm's short-run decisions than to the determination of the entire economy's employment level.

Keynes nevertheless argued that wages and employment are not determined solely by the marginal productivity of labor. Aggregate demand, expectations, investment, and output also influence employment.

Thus, Keynes defended the analytical usefulness of marginal productivity while rejecting the classical conclusion that the economy automatically reaches full employment through flexible wages.

The classical and Keynesian theories differ fundamentally in their explanations of employment and unemployment.

Classical theory:

• Full employment is the normal condition.
• Flexible wages and prices clear labor and goods markets.
• Saving is transformed into investment through changes in the interest rate.
• Say's Law implies that general overproduction is impossible.
• Unemployment is mainly voluntary or temporary.

Keynesian theory:

• Equilibrium can occur below full employment.
• Employment depends on effective demand.
• Wages may be rigid, especially downward.
• Saving and investment are influenced by different motives and may not be equal automatically.
• Involuntary unemployment can persist.
• Government intervention may be necessary to restore demand.

In summary, classical economics emphasizes supply-side adjustment and market self-correction, whereas Keynesian economics emphasizes aggregate demand, uncertainty, and the possibility of prolonged unemployment.

Keynes explained capitalist depression as a major deficiency of effective demand, especially investment demand. A downturn may begin when expectations about future profitability become pessimistic.

Cumulative process of depression:

• A fall in expected profitability reduces investment.
• Lower investment reduces aggregate demand.
• Reduced demand causes firms to cut production and employment.
• Lower employment reduces household income and consumption.
• The multiplier process creates a further decline in national income.
• Falling sales and increasing uncertainty further depress investment.

The crisis can be intensified by falling asset prices, debt burdens, and a liquidity preference for money. Monetary policy may become ineffective if interest rates are already very low and the economy is in a liquidity trap.

Keynes therefore viewed depression as a demand failure rather than merely a temporary adjustment in relative prices. Public investment and fiscal expansion may be required to break the downward spiral.

The paradox of thrift states that an attempt by everyone to save more may reduce total saving by lowering income.

Suppose households decide to consume less and save more. Initially, this appears beneficial for each household. However:

• Lower consumption reduces aggregate demand.
• Firms experience lower sales.
• Production and employment decline.
• Household incomes fall through the multiplier process.
• The final level of saving may not increase and can even decrease.

In a simple model, equilibrium income is:

If the marginal propensity to consume falls because households attempt to save more, equilibrium income declines when investment remains unchanged.

The paradox does not mean saving is always harmful. Saving can finance investment in the long run. Keynes's point is that, during a recession, simultaneous increases in desired saving may reduce income and prevent the economy from achieving higher actual saving.

Fiscal policy uses government expenditure, taxation, and transfers to influence aggregate demand. Keynes considered it especially important when private investment is weak.

Expansionary fiscal policy:

• Increase government expenditure.
• Reduce taxes.
• Increase transfer payments.

The initial rise in expenditure creates additional income, and the multiplier process produces a larger total increase in national income:

where is the government expenditure multiplier.

Effectiveness depends on:

• The marginal propensity to consume.
• The extent of spare capacity.
• The response of investment to income.
• The size of imports and taxes.
• The speed and targeting of government expenditure.

Fiscal policy may be less effective if it causes inflation, raises interest rates, crowds out private investment, or produces unsustainable public debt. Nevertheless, during a deep recession with unused resources, deficit-financed public spending can significantly increase output and employment.

Monetary policy changes the money supply and interest rates to influence investment, consumption, output, and employment.

Expansionary monetary policy may:

• Increase the money supply.
• Reduce the interest rate.
• Encourage investment and interest-sensitive consumption.
• Increase aggregate demand and employment.

However, its effectiveness is limited by several factors:

• Investment may be driven more by expectations than by interest rates.
• Banks may be unwilling to lend during a crisis.
• Firms may refuse to invest when expected demand is weak.
• In a liquidity trap, people hold additional money rather than purchasing bonds or goods.
• Monetary expansion may generate inflation once the economy reaches capacity.

Therefore, monetary policy can be useful in normal conditions, but Keynes argued that fiscal policy may be more reliable during severe depression, particularly when interest rates are already very low.