Background
The Harrod–Domar growth model examines the dynamics of economic growth through the interplay of capital, labor, and saving rates. Originating from the works of Roy Harrod and Evsey Domar, this model serves as a fundamental framework for understanding the requirements for balanced growth within an economy.
Historical Context
The model was developed independently by Roy Harrod in 1939 and Evsey Domar in 1946, during a period when economists were intensely debating the drivers of economic growth and stability. These post-Keynesian theorists sought to incorporate ideas from John Maynard Keynes’ earlier work into a more comprehensive growth model.
Definitions and Concepts
The Harrod–Domar growth model relies on several key assumptions and variables:
- Fixed Capital–Labour Ratios: The model assumes that the proportion of capital to labor (measured in efficiency units) remains constant.
- Saving Propensity: The portion of income that individuals save is fixed.
- Natural Growth Rate (n): The labor force grows at an exogenously determined, natural rate.
- Capital–Output Ratio (v): This ratio is assumed to be constant.
- Propensity to Save (s): This fixed rate determines the amount of national income saved.
- National Income (Y): Measured to determine savings (sY) and desired capital stock (vY).
- Warranted Growth Rate (w): Defined as w = s/v, the growth rate needed to maintain equilibrium between savings and investment.
Major Analytical Frameworks
Classical Economics
The Harrod–Domar model does not fit precisely within classical economics, which typically assumes flexible ratios of capital to labor and where market forces ensure full employment.
Neoclassical Economics
While neoclassical models often emphasize flexible production functions and marginal productivity, the fixed ratios in the Harrod–Domar model contrast sharply with these principles.
Keynesian Economics
This model significantly aligns with Keynesian economics, particularly in its emphasis on the roles of savings and investment in driving economic growth. The fixed parameters also resonate with Keynesian ideas about less-than-perfect flexibility in markets.
Marxian Economics
Marxist economics, with its focus on the dynamics of capital accumulation and class relations, does not fundamentally align with the Harrod–Domar model, though the focus on capital intensity is a shared trait.
Institutional Economics
Institutional economists would critique the model’s rigid assumptions about saving behavior and capital–labor ratios, pointing out the role of broader institutional factors in economic growth.
Behavioral Economics
Behavioral economics, with its focus on irrational and varied human behaviors, would challenge the notion of fixed saving propensities and capital-output relations embedded in this model.
Post-Keynesian Economics
Post-Keynesians endorse the theoretical lineage of the Harrod–Domar model, particularly its exploration of growth and instability. They may, however, seek to expand its applicability by relaxing some of its stringent assumptions.
Austrian Economics
Austrian economists might critique the overreliance on fixed parameters and the lack of adaptive responses within the economy, emphasizing instead the dynamic and entrepreneurial aspects of economic growth.
Development Economics
The Harrod–Domar model has had significant implications in the field of development economics, particularly during the 1950s and 1960s when it was used to estimate the required savings rates for achieving sustained economic growth in developing countries.
Monetarism
Monetarists, while focusing on the role that money supply plays in economic growth, would likely argue that the Harrod-Domar framework overemphasizes structural parameters without enough consideration of monetary factors.
Comparative Analysis
To understand the Harrod–Domar model better, it is often compared to the Solow growth model, which lacks fixed capital-labor and savings assumptions, allowing for different combinations of savings rates and natural growth rates.
Case Studies
- Post-War Reconstruction in Europe: The Harrod–Domar model was used to assess the capital requirements and targeted growth rates for the reconstruction of European economies after World War II.
- Developing Economies: Many developing countries have applied this model to plan their growth by estimating necessary rates of savings and investments.
Suggested Books for Further Studies
- Harrod, Roy. Towards a Dynamic Economics (1948)
- Domar, Evsey D. Essays in the Theory of Economic Growth (1957)
- Sen, Amartya. Growth Economics (1970)
Related Terms with Definitions
- Solow Growth Model: An endogenous
