GTAP模型应用的一个介绍.ppt

An introduction to GTAP applications relevant to ESCAP analytical work in trade A series of information sharing sessions on knowledge acquired through individual training Mia Mikic, TID More information on / Overview on presentation Why opting for a general equilibrium analysis? applied / computable general equilibrium models Why GTAP? Uses for ESCAP analytical work Models Model is a stylized simplification of reality in which behavior is represented by variables and by assumptions about how they are determined and interact. They allow us to frame the analysis in such a way that we are able to think consistently and logically about complex issues, to work out how changes in an economic system matter, and (sometimes) to make predictions about economic performance. General equilibrium Old idea: Walras (1874), Edgeworth (1881), Arrow and Debreu (1954) X X1 Y1 Y U A situation where all markets in an economy are simultaneously in equilibrium, that is, where prices and quantities do not change. p E Partial equilibrium Marshall (1890) Equality of supply and demand in only a subset of an economys markets -- usually just one -- taking variables from other markets as given. p q D S q1 p1 e Evaluation of trade liberalization Partial equilibrium models were most commonly used (at least until relatively recently) Standard presentation for a so-called “small country fiction”: a c b d So we opt for GE analysis for Theoretical consistency (Walras) Accounting consistency (no double-counting) Inter-industry effects (inter-country effects) Welfare analysis vs. prices/surpluses Perspective ?Better informed debate and policy analysis When not to use GE? Interest in one sector only Interest in introducing a very complex interpretation of one sector/industry Data not available Time is not available ? SOFTWARE What is CGE /AGE analysis? DATA NEW DATA / SOLUTION CONCLUSIONS THEORY/ MODEL POLICY/ SHOCK IN OUT GTAP Global Trade Analysis Project - Developed an