Three essays on investment-specific technical change and economic growth

This thesis investigates the relation between investment-specific technical change and long-run economic growth. The first essay points out the discrepancy between the steady state growth theorem and recent economic growth driven by information technology. Previous study finds that investment-specific technological progress accounts for 58% of economic growth in the U.S. However, their result hinges on the assumption of the Cobb-Douglas production function. This paper employs the CES production function to investigate the effect of investment-specific technological progress on long-run economic growth. In the steady state, quality improvement in each vintage is directed to expand more functions in one machine, resulting in contraction in the types of capital. The offsetting effect between quality and variety implies that the relative capital income share is constant in the steady state. Empirical tests for the U.S. data show that log capital income is cointegrated with log labor income, indicating that investment-specific technological progress does not generate long-run economic growth. We also estimate the elasticity of substitution between capital and labor and the offsetting effect using aggregate data. The results report that the elasticity of substitution is significantly less than one, and that there is an offsetting effect to investment-specific technological progress.; The second essay investigates the quality changes in capital and labor inputs across 46 industries from 1968 to 2001. We incorporate a time-varying quality measure to the efficiency units of capital. The result indicates that the average quality of capital assets over time has improved 46 percent in the cross industry average. The quality improvement effect accounts for 30 percent in the total growth of the efficiency units of capital. Although the net quantity effect is still the largest component in the growth of the efficiency units of capital, there is significant substitution among different vintages and asset types as well. The average quality growth in the efficiency units of labor is 17 percent, and it is negatively associated with the total hours worked.; The third essay investigates unbalanced growth facts and their implications for existing growth theory. We find that the balanced growth implication is consistent with data for the United States at the national aggregate level, but not at a more disaggregate level and internationally. Among the various unbalanced growth facts, the increases in the depreciation rates of equipment and of aggregate capital have the most significant impact on the growth theory. Under the Cobb-Douglas framework, an increasing depreciation rate of equipment can result in rising, constant, or declining rate of return of equipment, depending on the magnitude of the decreasing net marginal product effect and the capital loss effect. If either of the two effects is greater, it is possible to reconcile the increasing consumption-output ratio, increasing depreciation rate, and the rising equipment-structure ratio.