广义Armington替代弹性模型的拓展构造与中国贸易发展的预期应用研究

Armington elasticity of substitution is one of the key parameters in international economics, but the basic model still remains unchanged for about half a century, which seriously deviated from the reality of monopolistic competition, the rapid trade development of the heterogeneity of product. So it leads to the estimated results seriously biased. This project plans to extend and construct generalized Armington elasticity of substitution models from the macro, meso and micro levels. Based on different levels of product categories, China's extended Armington elasticities are measured. Then this project will calibrate the traditional Armington elasticity of substitution, establish a fundamental, nonprofitable and prospective database for Armington elasticity of substitution, and enrich the international economics theories. Refining out some major trade development problems which are closely related to the Armington elasticity, including the welfare issues of RCEP which is going to be signed up soon, trade and climate protection issues which is concerned globally, Trade Facilitation Agreement which has taken into effect recently in WTO and replacing business tax (BT) with value-added tax (VAT) issues which is extremely important and so on. Using the CGE, GSIM and panel data models studies these problems with the calibrated Armington elasticity. According to the research conclusions, this project puts forward some policy recommendations to accelerate the development of trade and to implement the ‘Five Development Concepts’ including ‘opening up’, ‘sharing’ and ‘green development’.

阿明顿（Armington）替代弹性是国际经济学的关键参数之一，但其基本模型仍停留在近半个世纪以前，严重脱离垄断竞争、异质性产品贸易发展迅速的现实，以此估计的结论严重有偏。本项目拟从宏观、中观和微观层面拓展并构造广义阿明顿替代弹性模型，基于不同层次产品分类，测算中国广义阿明顿替代弹性，校正传统的阿明顿替代弹性，建立具有基础性、公益性、前瞻性学术价值的阿明顿替代弹性数据库，丰富国际经济学理论。提炼出与阿明顿替代弹性密切相关的重大贸易发展问题，包括即将签署的《区域全面经济合作伙伴关系协定》福利问题、全球关注的贸易与气候保护问题、WTO近期生效的《贸易便利化协定》问题、牵一发而动全身的“营改增”问题等，采用CGE、GSIM、面板数据模型等方法，将校正后的阿明顿替代弹性值应用于研究这些问题。依据研究结论，提出加快促进贸易发展和实施包括“开放”、“共享”、“绿色”在内的“五大发展理念”的政策建议。

一、项目的背景. Armington替代弹性是与贸易成本、贸易便利化等贸易政策密切相关的重要参数。先前对该参数的估计严重脱离进口来源国产品之间异质性的现实，使得估计该参数的结果严重有偏。本项目对其估计方法进行拓展、完善，运用该估计值测算贸易福利等。.二、主要研究内容、重要结果与关键数据.基于拓展的Feenstra框架，测度统计用 39 种工业品的Armington宏观、中观、微观替代弹性，以及中国进口需求关于人民币汇率的弹性，分析宏观替代弹性的决定因素，结果是：大多数这些工业品的三种替代弹性没有显著差异，增加进口贸易伙伴使得部分产品宏观替代弹性发生显著变化，人民币升值会使进口需求额减少且大部分行业差异性不大，宏观替代弹性的决定因素主要是本地偏好和进口配额。.运用优于传统FBW 的混合估计法估算了19 种统计用农产品Armington 微观替代弹性，运用该估计值测算农产品进口种类增长的消费者福利，结果是：在产品质量不变与变化两种情况下，农产品进口种类增加都使得我国进口福利增加，但是在质量变化情况下的进口福利增加幅度小于质量不变情况下的进口福利增加幅度。.运用混合估计法估算了3667个HS6 位数产品层次上的Armington 微观替代弹性，考察了Armington 宏观替代弹性、国内生产率对进口产品种类利得的影响，测算了中国工业品贸易利得的偏误，结果是：中国国内生产率会放大贸易成本对进口产品种类的影响；Armington宏观替代弹性越高，贸易成本对进口产品种类的影响越大；中国工业平均贸易利得被高估12%，国内生产率导致的平均贸易利得被高估9%；从行业结构看，有12个行业的进口利得被低估或高估，其中“煤炭”贸易利得被高估3~5倍。 .运用KAM法测算7690种HS8位码产品进口需求弹性值和Armington宏观替代弹性值，建立相应数据库，并报送财政部关税司。.三、科学意义 . 拓展了传统Armington 替代弹性内涵及测算方法，估计了多层次产品、产业的广义Armington替代弹性值，建立了数据库，运用这些值分析中国经贸领域重要现实问题，得到一些重要结论，延伸了国际贸易理论与政策的研究。