中文摘要：

货币政策工具的作用效率是动态变化的。本文利用状态空间模型，以1999年12月至2008年8月的月度数据为样本，对我嗣货币政策工具的时变效率进行研究，得出结论：在样本区间内，我国货币政策IT具的整体作用效率不高。其中，利率、外汇占款的作用相对较高，冉贷款，准备金率的作用效率低，且变动不稳定。此外，货币政策工具的作用效率与货币政策状态间存有一定的关联，其抑制经济过热的效率优于启动经济的效率。

英文摘要：

Monetary policy tools＇ efficiency was dynamic. With the method of State Space Model, using monthly data between December 1999 and August 2008, this paper tests the time-varying efficiency of China＇s monetary tools, and finally indicates that the efficiency of China＇ s monetary tools was low in general. However, efficiency of interest rate, RMB counterpart of foreign exchange purchase was relatively high, while the efficiency of the required reserve ratio and re-loan was low and unstable. Besides, there is certain relation between monetary policy tools＇ efficiency and monetary state, namely, the efficiency of suppressing an over-heated economy is higher that that of stimulating a weak economy.