本文使用貨幣搜尋模型分析人們對支付工具的選擇, 以及在多重支付工具的競爭下貨幣政策對流動性和總體經濟活動的影響。我們以訊息障礙刻畫不同資產: 現金有被偷的風險, 而轉帳卡的使用必須依賴紀錄與監督的技術。當轉帳卡的接受度(存款的流動性) 為內生決定時, 經濟體具有複均衡, 而通貨膨脹在複均衡中對流動性與產出的影響迥異, 在轉帳卡接受度較低的均衡, 通貨膨脹率上升提高存款的流動性和經濟體的總產出, 這與轉帳卡接受度為外生給定的情況截然不同。因此, 是否將資產的流動性予以內生化對貨幣政策意涵有重大的影響。

We consider a search monetary model with currency and a bank depositbased
payment instrument such as debit cards, in which means-of-payment
decisions and liquidity of assets are modeled explicitly. Currency is subject to thefts, while costly technology of record keeping and monitoring is needed for accepting debit cards. When the acceptability of debit cards (which implies liquidity of bank deposits) is endogenously determined, there may exist multiple equilibria. In the equilibrium with a lower acceptance rate of debit cards, higher inflation raises the liquidity of bank deposits and output, in contrast to the case in which the acceptability of debit cards is exogenously imposed. Hence, the question of whether to endogenize the acceptability of means of payment has monetary policy implications.