Which of the following growth theorists is best known for developing a model that explicitly embodied technical change into new capital goods (the "Vintage Approach")?

1. Understanding the Concept To answer this question, it is essential to distinguish between the two main types of technical progress discussed in economic growth literature:

• Disembodied Technical Change: This refers to improvements that increase the productivity of all existing factors of production (capital and labor) simultaneously. It is "manna from heaven"—it doesn't require new machines. Solow’s original 1956 model used this approach.
• Embodied Technical Change: This refers to technological improvements that are built into new machinery and equipment. In this view, older machines do not benefit from new technology; only the newest "vintages" of capital are highly productive.

Why Robert Solow? While Robert Solow is famous for his 1956 neoclassical growth model (which initially used disembodied progress), he published a seminal paper in 1960 titled "Investment and Technical Progress." In this later work, he introduced the Vintage Model . He argued that technical progress is "embodied" in new capital assets. To improve productivity, an economy must invest in new machines that carry the latest technology. This shifted the focus from just "amount of capital" to the "age and quality of capital." Analysis of Other Options

• Roy Harrod (A): Developed the Harrod-Domar model, which focuses on the "knife-edge" equilibrium between savings and the capital-output ratio. While he discussed "Neutral Technical Progress," his model did not utilize the embodied/vintage framework.
• Nicholas Kaldor (C): Known for the Technical Progress Function , where he argued that technical progress and capital accumulation are inseparable. While his ideas are related to the idea that investment drives technology, the specific formalization of "Embodied Technical Change" via the vintage approach is a hallmark of Solow’s 1960 work.
• Joan Robinson (D): A post-Keynesian who criticized the neoclassical production function (the "Cambridge Capital Controversy"). She focused more on the "Golden Age" of growth and the problems of measuring capital rather than formalizing embodied technical change models.