2023-05-30-NBER-中央银行数字货币的简单模型_64页_447kb

This paper develops a simple general equilibrium model to analyze the trade-offs between physical cash and central bank digital currency (CBDC). Key differences between cash and CBDC include transaction efficiency (CBDC has lower costs), tax evasion possibilities (cash allows evasion, but with risk), and potential nominal returns (cash has zero return, while CBDC can be positive or negative). The model establishes conditions for the coexistence of both forms and shows how government policies, such as tax rates, penalties for evasion, and CBDC returns, influence their relative holdings.

Results indicate that the share of CBDC is highly sensitive to its nominal return—the strongest driver among all policies tested. Other factors, like transaction efficiency and tax policies, also affect holdings but with varying impacts. The model demonstrates that CBDC can facilitate negative interest rates and helicopter drops, enhance welfare through policy adjustments, and mitigate capital flight by structuring returns appropriately. Cash persists due to privacy concerns and unmet needs for inclusion among the poor, even with the advantages of CBDC. The framework offers insights into designing CBDC to balance monetary policy, financial stability, and privacy.