中国居民消费/储蓄行为的一个理论模型

A Theoretical Model of China’s Residential Consumptiaon(Saving)Behavior

本文在随机动态优化的框架下，考虑中国经济的具体特征，重新建立了我国居民消费／储蓄行为的理论模型。其要点是：消费支出本身就具有外生不确定性；“摸着石头过河”改革中制度变量的演进具有马尔科夫性。在一般性的不确定性设定下，我们解出了解析解并论证：支出和收入的双重不确定性增强了居民的预防性储蓄动机，中国式改革的性质导致了消费的过度敏感性，我国平均消费倾向将呈现一个“U”形变动。文章最后给出了刺激消费的政策建议。

Under the framework of stochastic dynamic optimization, the paper constructs a theoretical model of residential consumption （saving） behavior in China. Key premises in- clude ： exogenous uncertainty is embodied in consumption expenditure, and institutional variables under the reform strategy of crossing the river by feeling the stones follow a Markov process. Analytical solutions are derived under general settings about uncertainty and it is found that i） dual uncertainties embodied in expenditure and income strengthen the precautionary motive of residents; ii） Chinese style reform induces over-sensitiveness of consumption; and iii） China＇s average consumption propensity tends to exhibit a U-type time path. Policies to stimulate consumption are provided in the end.