Abstract: As an empirical research method, input-output technique is widely used in the analysis of practical economic problems, but the understanding of the assumptions and properties of the model is the premise of correct use of the method The prominent characteristics of input-output model are productioncentered, structured and systematic Demanddriven quantity model and costdriven price model constitute the core framework of input-output technique, both of which are productioncentered The interaction between industries reflected in the quantitative model and the price model includes not only direct but also indirect connections, therefore it is a structural methodology From the systematic point of view, this framework takes production as the core to form the endogenous boundary of the model and can further adjust the endogenous boundary and concept In addition, the supply driven model is established by introducing distribution coefficient, and Leontief inputoutput model is extended to generalized inputoutput model by being combined with optimization model, which constitute the systematic frameworkFocusing on the basic properties of inputoutput model, this paper fully discusses some basic issues of the framework, including the nature of structural description, the determination and adjustment of the endogenous boundary of the system, the symmetry of the demanddriven and supplydriven modelling system, and the duality of the generalized input-output system From the discussion, the thoughts of the authors on the properties of input-output framework are proposed

Key words: inputoutput, structural analysis, supply driven, duality

摘要： 投入产出方法作为一种经验研究方法被大量用于实际经济问题的分析，但是模型假定与方法性质的理解却是合理使用投入产出方法的前提。投入产出模型的突出特点表现为以生产为中心、结构性和方法的系统性。投入产出需求拉动的数量模型和成本推动的价格模型构成了其核心分析框架，两类模型都是以生产为中心；数量模型和价格模型所体现的产业间相互影响不仅包括直接联系，也包括间接联系，从而具有结构性特征。从系统性来看，这一分析框架以生产为核心形成模型的内生边界，并可以进一步对内生边界和概念进行调整；此外，通过引入分配系数建立供给驱动模型，以及与优化模型相结合扩展为广义投入产出模型体系，构成系统性的分析框架。为此，本文从投入产出模型的基本性质出发，对投入产出方法结构性的内涵、模型系统内生边界的划分和调整、需求拉动和供给推动模型体系的对称性，以及广义投入产出体系的对偶性等若干基本问题展开充分讨论，由此提出笔者对投入产出方法性质的思考。

关键词: 投入产出, 结构分析, 供给驱动, 对偶