央行数字货币还是现金--基于隐私需求视角的分析  

Central Bank Digital Currency or Cash--An Analysis Based on Privacy Concern

作　　者：贾鹏飞 JIA Pengfei(Nanjing University,210093)

机构地区：[1]南京大学商学院,210093

出　　处：《财贸经济》2024年第5期41-53,共13页Finance & Trade Economics

基　　金：国家自然科学基金青年项目“宏观审慎政策的理论依据与最优政策设计”(72104101)。

摘　　要：我国数字人民币定位于现金类支付凭证(MO),强调与传统现金之间的替代和互补关系。深入研究央行数字货币与现金的关系具有重要的现实意义。本文通过构建世代交叠模型研究央行数字货币和现金的选择问题。央行数字货币“基于账户”的特点反映了其不具备完全的匿名性,在经济个体需要隐私的环境中,持有央行数字货币将产生隐私成本。然而,央行数字货币“电子货币”的特点使其可以获得大于零的利息。因此,经济个体将在央行数字货币和现金间权衡。基于经济个体的不同选择,本文刻画了央行数字货币和现金共存的经济环境。本文进一步分析货币政策冲击、偏好冲击以及隐私成本冲击对央行数字货币和现金的动态影响。在模型中,外部冲击将从集约边际和广延边际两个维度来影响央行数字货币和现金的需求。本文发现,央行数字货币利率的增加将导致央行数字货币总需求增加,现金总需求减小。偏好变量的增加将使央行数字货币总需求增加,但其对现金总需求的影响难以确定。隐私成本的增加将导致央行数字货币总需求减小,现金总需求增加。本文的研究为中央银行有效处理央行数字货币与现金的关系提供了政策建议。As a major innovation in the history of central banking,Central Bank Digital Currency(CBDC)will have great impact on the payment system and the macroeconomy.In China,CBDC,known as e-CNY,is positioned as Mo,and it can have significant substitution effects and complementary effects on cash.Comparing CBDC and cash thus has important policy implications.This paper studies CBDC and cash,through the lens of an overlapping generation model under which,we assume that agents demand privacy.Agents consume and save,and they have two saving vehicles:CBDC and cash.CBDC is not anonymous,and hence carrying CBDC incurs a privacy cost.However,CBDC has the potential of bearing an interest.Cash is anonymous,and using cash can protect the agent's privacy.But the nominal yield for cash is zero.Agents then consider the trade-offs of using CBDC and cash.In the model,agents are heterogenous in terms of their endowment.We show that agents with low endowment choose to use CBDC,whereas agents with high endowment choose to use cash.Thus,in the model,we find that CBDC and cash can co-exist.We then explore the effects of monetary policy shocks,preference shocks,and privacy cost shocks on the demand for CBDC and cash.In this paper,exogenous shocks affect CBDC and cash through both intensive and extensive margins.The research results show that,the increase in CBDC interest rate makes CBDC more attractive than cash,which in turn leads to an increase in the demand for CBDC while a decrease in that for cash.In addition,as the preference shifter goes up,agents increase their savings.We show that in this case,aggregate demand for CBDC increases whereas that for cash is unclear.Finally,we study the case in which privacy cost increases.We find that as privacy cost goes up,the average return of CBDC falls,and as a result the agents demand more cash and less CBDC.Our paper makes three contributions to existing literature.First,while existing literature often studies CBDC and bank deposits,this paper focuses on CBDC and cash,and as noted above,comparing

关 键 词：央行数字货币 现金 个人隐私 世代交叠模型 

分 类 号：F820[经济管理—财政学]