We study the effects of non-sterilized intervention on a spot foreign exchange (forex) rate using a multi-period game-theoretical model which involves an unspecified number of competitive traders, a finite number of strategic traders (forex dealers) with heterogenous initial money balances, and the central bank of the home country. Simulating the subgame-perfect Nash equilibrium of the two-stage game played by the forex dealers in each period, we show that the non-sterilized intervention of the central bank may lead to a perverse effect on the spot forex rate. We call the mechanism underlying this effect strategic trade switching channel that works when an increase in the central bank’s forex currency demand (supply) exerts such a big upward (downward) effect on the forex rate that some sufficiently big dealers, who optimally bought (sold) forex currency in the previous period when the forex rate was sufficiently low, find in the current period selling (buying) it more profitable, thus moving the forex rate in a direction undesired by the central bank. JEL Classification: D43, F31, G20

中文翻译：

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非灭菌干预对即期汇率的不利影响

我们使用多期博弈理论模型研究非灭菌干预对即期外汇（forex）汇率的影响，该模型涉及未指定数量的竞争交易者，有限数量的战略交易者（外汇交易商）和不同的初始资金余额和母国中央银行。通过模拟外汇交易商在每个阶段进行的两阶段博弈的亚博弈完美纳什均衡，我们表明，中央银行的非灭菌干预可能会导致即期外汇汇率产生不利影响。我们称这种效应为基础的机制是战略贸易转换渠道，当中央银行的外汇货币需求（供给）的增加对外汇汇率产生如此大的向上（向下）影响以至于一些足够大的交易商时，这种机制就起作用了 当外汇汇率足够低时，他在上一时期最佳地购买（出售）了外汇货币，然后发现在当前时期卖出（购买）了该货币，这使得外汇汇率朝着中央银行所不希望的方向发展。JEL分类：D43，F31，G20