演講者簡介 : 蔡宜展先 生為Ph.D. in Economics，The Ohio State University (June 2010 expected)。其主要研究領域為Macro and Monetary Economics、Computational Economics。現正申請本所研究職務中。
演講摘要 : I study the macroeconomic response to news of future technological innovation under the assumption that firms cannot frictionlessly shift from existing capital stocks to new varieties associated with the impending advance in technology. Combining this new element with variable capital utilization and preferences designed to minimize wealth effects on labor supply, I develop a model that simultaneously accounts for four stylized facts: (1) slow diffusion of new technologies, (2) lumpiness in microeconomic investment, (3) stock prices leading measured productivity, and (4) comovement of consumption, investment and labor hours. On news of a coming technological innovation, firms begin to invest in new capital goods which will allow them to benefit from the innovation once it arrives. Because fixed costs lead some to delay adoption, there is slow diffusion of the new technology. At the firm level, investment in new technology follows an (S, s) rule, and at the aggregate level the model generates a hump-shaped investment pattern typical of the data. Moreover, the introduction of new capital causes the price of old capital to fall, leading stock prices to rise on news of the new technology. Finally, variable capital utilization slows the onset of diminishing returns to labor, so that work hours rise instantly, permitting increases in both consumption and investment.
