外生冲击、居民福利与最优财政支出规则选择

Economic Exogenous Shocks,Residents’Welfare and Optimal Fiscal Expenditure Rules

如何利用财政支出规则应对外生冲击,已有的研究大多从平抑波动视角出发,对居民福利关注不够,且忽略了不同支出的相互配合。文章基于居民福利视角,采用NK-DSGE模型考察了当三类外生冲击发生时,政府消费、投资以及转移支付的最优规则组合。从抑制消费波动角度看,在技术或投资受到正向冲击时,平滑性财政支出规则为最优选择;在劳动偏好受到负向冲击时,盯住债务的支出规则为最优。从居民福利最大化角度看,在技术遭受正向冲击时,最优规则为三类支出均采用平滑规则;在劳动偏好遭受负向冲击时,最优规则为消费性支出采用盯住产出逆向调节,投资性支出与转移支付采用盯住债务与产出逆向调节;在投资效率遭受正向冲击时,最优规则为消费性支出采用盯住产出逆向调节,投资性支出采用盯住债务和产出逆向调节,转移支付采用盯住债务逆向调节。研究表明,给予不同类型的财政支出以不同的应对规则,增加政策的灵活性和精准性,可以更好地应对风险冲击,保障居民福利。

How to use fiscal expenditure rules to deal with exogenous shocks,most of the existing studies start from the perspective of stabilizing economic fluctuations,pay insufficient attention to residents’welfare,and mostly investigate the single fiscal expenditure rule of total amount,ignoring the cooperation between different types of fiscal expenditure.Based on the new Keynesian model(NK-DSGE),assuming that the economic operation is subject to three kinds of exogenous shocks of different nature,this paper analyzes and evaluates the optimal fiscal expenditure rules and their combination from the perspectives of stabilizing consumption fluctuations and ensuring residents’welfare.Specifically,this study divides public expenditure into government consumption expenditure,government investment expenditure and transfer payment expenditure,and evaluates the welfare guarantee effect of the above expenditure under the smoothing rule,the output-oriented reverse adjustment rule,the debt-oriented reverse adjustment rule and the simultaneous output-oriented and debt-oriented reverse adjustment rule respectively.The specific conclusion is that:From the perspective of restraining consumption fluctuation,when production or investment is positively impacted,the smooth rule is the best choice;when labor preference is negatively impacted,the debt-oriented rule is the best choice.From the perspective of maximizing residents’welfare,and based on the comprehensive evaluation of long-term welfare effect and short-term welfare effect,under the positive impact of technology on production,the optimal rule is that the smoothing rule is adopted for all three types of expenditure;under the negative impact of labor preference,the optimal rule is that consumption expenditure adopts output-oriented reverse adjustment,and investment expenditure and transfer payment expenditure adopt both output-oriented and debt-oriented reverse adjustment;under the positive impact of investment efficiency,the optimal rule is that consumption expenditure adopts output-oriented reverse adjustment,investment expenditure adopts both output-oriented and debt-oriented reverse adjustment,and transfer payment adopts debt-oriented reverse adjustment.Finally,this paper verifies that when consumption expenditure is biased towards the field of people’s livelihood and increases the substitution elasticity of public consumption and private consumption,the welfare level of residents can be significantly improved.In the post epidemic era,the uncertainty of world economic development has greatly increased.This study shows that,compared with the single fiscal expenditure rule of total amount,different types of fiscal expenditure are given different response rules according to the specific nature of exogenous shocks,so as to increase the flexibility and accuracy of policies,better deal with the uncertainty in the future,and ensure residents’welfare to the greatest extent.