This paper analyzes the impact of the interaction between monetary policy and fiscal policy on the stability of an one-sector AK economy. The monetary authority pegs the money growth factor while the fiscal authority implements a progressive consumption tax. The demand of money is motivated by a fractional liquidity constraint on consumption expenditures. When only the monetary authority operates, the unique steady state is locally indeterminate if the intertemporal elasticity of substitution in consumption is low enough. When the fiscal authority is introduced, the interaction of fiscal policy and monetary policy modifies significantly the stability properties. In particular, the fiscal authority could either stabilize or destabilize the economy depending on the tax progressivity, the strength of the liquidity constraint and the intertemporal elasticity of substitution. Our numerical examples further verify those theoretical results.

本文分析了货币政策和财政政策之间的相互作用对一部门AK经济稳定性的影响。货币当局盯住货币增长因素，而财政当局则征收累进消费税。货币需求是由对消费支出的部分流动性约束所激发的。当只有货币当局运作时，如果消费替代的时间跨度弹性足够低，则唯一的稳态将是局部不确定的。当引入财政当局时，财政政策和货币政策的相互作用会极大地改变稳定性。特别是，财政当局可能会根据税收累进性来稳定或破坏经济，流动性约束的强度和替代的跨期弹性。我们的数值示例进一步验证了这些理论结果。