本文重新考察了Elbadawi（1994）模型中吸收率的决定因素，认为Elbadawi（1994）模型只是从需求角度对吸收率的决定因素进行了论证。因此，本文从供给角度运用Balassa-Samulson模型对Elbadawi（1994）模型作了改进，引入了生产率因素，解决了吸收率的内生决定机制。在此基础上，根据均衡分析的思路，本文得出了均衡吸收率的决定因素，从而证明了相对生产率与Elbadawi（1994）的相容性，为均衡汇率的测算提供了理论基础。同时，本文基于BEER通过1980-2007年的季度数据对人民币均衡实际汇率进行了测算，证实了扩展的Elbadawi（1994）相对于其它模型的优越性。

The supposed undervaluation of the renminbi has been the subject of intensive academic research over the past few years. Using equilibrium exchange rate models (Purchasing Power Parity, BEER and FEER), many authors have concluded that the renminbi is undervalued by 15 to 30% against the dollar. This article shows that the common view is not that obvious. The models used in the estimation (BEER or FEER) assume that the economy is at full-employment, a strong hypothesis for developing economies such as China, whose unemployed amount to 150 million people. On the contrary, we show that China is facing massive unemployment and if investment depends on expected potential demand (from domestic consumption and foreign demand), then an undervalued exchange rate (by traditional standards) is suited for its policy objectives. Therefore the exchange rate can be analyzed as a policy tool used by the Chinese authorities to pursue their objectives. The exchange rate can be undervalued by traditional standards and in equilibrium compared to the government's policy objectives. This article shows that equilibrium exchange rate theories are not suited for developing countries and therefore the concept of equilibrium exchange rate is highly questionable. The final section analyzes the adoption of a managed float regime by the Popular Bank of China and discusses the delicate issue of the best exchange rate regime for China.