Keynesian Macroeconomics

Focus: Examines macroeconomic equilibrium, particularly during periods of high unemployment, and explores the role of aggregate demand in economic downturns.
Relevant case study: The Great Depression, which serves as a focal point for Keynesian theories on economic recovery and government intervention.

Duration: The Great Depression lasted from 1929 to 1941, marking a significant downturn in economic activity in the United States and globally.
Impact on the U.S.: The official unemployment rate peaked at around 25%, leading to severe social and economic dislocation.
Emergence of "Hoovervilles": These were makeshift housing settlements for the homeless, named derisively after President Herbert Hoover, whom many blamed for the economic policies that failed to address the crisis.
Economic recovery: Significant recovery did not begin until World War II, which spurred massive government spending and job creation.

GNP Trends: During this period, Gross National Product (GNP) showed a declining trend, particularly from 1929 to 1935, where it dropped significantly and fell below pre-Great Depression levels.
Real GDP decline: The economy experienced a decrease of about 10% GNP relative to per capita income, highlighting the drastic impact on individual prosperity.

Debates: Economists began to question why the economy seemed unable to self-adjust and recover from downturns, as posited by classical economic theories.
Persistent unemployment: This situation was attributed to real wages exceeding equilibrium levels, making it difficult for labor markets to clear.
Neoclassical economists: They tended to dismiss the potential for fiscal policy to effectively raise GDP through increased aggregate demand, adhering instead to long-run growth predictions.

Winston Churchill: Critiqued government borrowing, indicating it acted as a disruptor to private enterprise and increased competition for scarce loanable funds, potentially raising interest rates.
Andrew Mellon: Advocated for systematic liquidation across various sectors, believing that allowing failing businesses to collapse would purify the economy and enhance moral living and hard work.

Critique of Neoclassical Theory: Keynes strongly criticized the assumptions of neoclassical economics, stressing the real-world implications of prolonged economic downturns and insufficient demand.
Support from other economists: He was supported by contemporaries like Joseph Schumpeter, who highlighted the shortcomings of the long-run recovery perspective and called for a reevaluation of macroeconomic theory.

Unemployment causes: Argued that unemployment primarily arises from inadequate demand rather than inflexible wages.
Inventory observation: Economic downturns prompt firms to notice unsold inventories, leading to layoffs that further reduce demand and income, causing a vicious cycle.
Stagnation: The failure to spend surplus income leads to a lack of information regarding future spending needs, exacerbating stagnation.

Marginal Propensity to Consume (MPC): Indicates that an increase in disposable income leads to increased consumption at a non-linear rate (0 < ΔC/ΔYd < 1).
Formula: The relationship is framed by the equation: C = consumption, Yd = disposable income, where ΔC/ΔYd = MPC, highlighting the bounded nature of consumption increases relative to income growth.

Linear relationship: The consumption function illustrates a direct linear relationship between disposable income and consumption across various examples—indicating that increases in disposable income positively correlate with increased consumption levels.

Marginal Propensity to Save (MPS): Reflects that the rate of savings increases at a rate lesser than that of income, also characterized by the equation 0 < ΔS/ΔYd < 1.
Economic identities: This relationship is distilled into the identities: ΔC/ΔYd + ΔS/ΔYd = 1, reinforcing the interconnectedness of consumption and savings within economic frameworks.

Consumption model: The Keynesian consumption function can be modeled as C = a + bYd, where 'a' represents autonomous consumption independent of income, and 'b' indicates the marginal propensity to consume.

Factors affecting consumption: Aside from present income, consumption decisions are influenced by accumulated past savings, access to credit, expectations of future income, and various social factors and standards.

Characteristics: Investment is understood as autonomous, driven more by external factors than by current income levels.
Key influences: Factors that impact investment decisions include investor expectations, levels of business confidence, and the prevailing political climate.

Simple Keynesian model: Expressed as Y = C + I, where total output is determined by the sum of consumption and investment.
Equilibrium output: The calculation of equilibrium output relies on the multiplier effect, articulated as 1/(1-MPS), showing how fiscal actions can stimulate economic activity beyond initial spending.

Gap calculations: Recessionary gaps are assessed by the difference between desired output at full employment and actual output levels during economic downturns.
Policy response: Economic policies must address these gaps through injections into the economy, such as increased government spending to stimulate demand.

Impact of savings on the economy: While individuals may aim to save more during downturns, collectively increased savings can paradoxically decrease overall consumption and lead to lower economic output, demonstrating a complex relationship between individual financial behavior and broader economic health.

Correlation: Empirical observations indicate a strong relationship wherein increased government spending can significantly boost economic activity, especially when amplified by the multiplier effect, stimulating both demand and supply.

Fiscal policies: A distinction is made between discretionary fiscal policies, which are actively chosen, and automatic stabilizers, which automatically adjust to counteract economic fluctuations during downturns.

Job Guarantee vs. Universal Basic Income: Contemporary discussions revolve around the implications of these approaches on economic stability, addressing issues such as full employment, income inequality, and the challenges of implementation within varying economic contexts.