高宏Chapter3A浅析.ppt

Chapter 3New Growth Theory 暨南大学经济学院 周泳宏 tzhouyhjnu@jnu.edu.cn introduction Remember: BGP in Solow model introduction The models we have seen so far do not provide satisfying answers to the questions about economic growth Capital accumulation cannot account for a large part of either long-run growth or cross-country income differences The only determinant of income is a mystery variable, the effectiveness of labor, A, whose meaning is not specified and whose behavior is taken as exogenous This chapter therefore investigates the fundamental questions of growth theory more deeply The accumulation of knowledge Interpreting the effectiveness of labor as knowledge Consider human as well as physical capital Differences in output for given amounts of physical and human capital Investigate the variations in institutions New Growth Theory （ Endogenous Growth Theory ） AK Model A elimination of decreasing marginal output of capital RD Model We need to model the allocation of existing resources between the production of goods and new knowledge which is produced by a research sector . Learning-by-doing The improvement in knowledge is a side effect of the standard production process and hence does not involve a specific R D sector. Human capital Model Physical capital is not the only form of productive capital. The skills and knowledge of the labor force is also a type of capital. extension The combination of endogenous saving and the models introduced above. Pat A Research and Development Models 3.1 Framework and Assumptions Overview We have seen that the effectiveness of labor represents knowledge or technology We introduce an explicit research and development (RD) sector Model the production of new technologies Model the allocation of resources between conventional goods production and RD Specifics Two sectors Goods-producing sector RD sector Think about θ θ0 Past discoveries may provide ideas and tools that make future discoveries easier θ0 Past discoveries make futur