Stochastic Growth Daron Acemoglu 经济增长导论课件.pdf

14.452 Economic Growth: Lecture 13, Stochastic Growth Daron Acemoglu MIT December 10, 2009. Daron Acemoglu (MIT) Economic Growth Lecture 13 December 10, 2009. 1 / 52 Stochastic Growth Models Stochastic Growth Models Stochastic Growth Models Brock and Mirman (1972): generalization of neoclassical growth and starting point of Real Business Cycle models Baseline neoclassical growth: complete markets, households and Örms can trade using any Arrow-Debreu commodity. Complete markets: full set of contingent claims traded competitively. Implies that individuals can fully insure against idiosyncratic risks. Source of interesting uncertainty thus is aggregate shocks. Bewley (1970s and the 1980s): households cannot use contingent claims and can only trade in riskless bonds. Explicitly prevent risk-sharing and thus ìincomplete marketsî. Stochastic stream of labor income: can only achieve smoothing via ìself-insuranceî. Does not admit a representative household; trading in contingent claims not only su¢ cient, but also necessary for representative household assumption with uncertainty. Key for study of questions related to risk, income áuctuations and policy. Daron Acemoglu (MIT) Economic Growth Lecture 13 December 10, 2009. 2 / 52 The Brock-Mirman Model Optimal Growth under Uncertainty The Brock-Mirman Model I With competitive and complete markets, the First and Second Welfare Theorems so equilibrium growth path is identical to the optimal growth path. But analysis is more involved and intr