人民币汇率与物价的非线性关系研究——基于傅里叶函数和滚动因果检验

本文通过选取2005年7月至2014年7月的月度数据,采用非线性傅里叶单位根检验和滚动因果检验实证研究了汇率与物价之间的关系。傅里叶单位根检验结果表明,人民币对美元实际汇率为非线性平稳时间序列且存在一个结构突变点,购买力平价成立。参数稳定性检验结果显示,人民币汇率与我国CPI间的二元VAR模型在长期内较为稳定,短期内存在结构性变化。通过动态因果检验得出,人民币汇率与我国CPI之间存在双向动态因果关系,而且二者之间的影响关系与经济周期密切相关,通货膨胀严重时期汇率的传导效应更强。     

人民币均衡实际汇率简约单方程模型实证分析

汇率作为开放经济的中心变量,其频繁的波动使各国对汇率及汇率制度安排重新进行了审视。在人民币持续升值压力的背景下,我国完成了由单一盯住美元向参照一篮子货币调节的汇率制度转变。但改革后人民币实际汇率的变动趋势如何?通过对影响均衡实际汇率的基本经济要素进行实证检验,分析了未来我国均衡实际汇率的变动方向,采用滤波方法估计了未来均衡实际汇率变动的基本方程。同时,为反映基本经济要素对均衡实际汇率的经济解释力,还运用脉冲反应函数进行实证检验。     

实际汇率贬值的经济增长效应研究——分样本国家检验

传统观点并未将实际汇率作为影响经济增长的核心变量之一,但"罗德里克新论"的出现肯定了汇率贬值对经济增长的积极作用。本文实证检验了实际汇率贬值的经济增长效应在不同样本国家中的检验情况,发现经"巴萨效应"修正后得到的实际汇率每贬值10%,经济将增长0.93%。分组检验的结果显示:(1)"贬值促增长"这一结论对发达国家不适用,其实际汇率偏离通常短暂地存在于市场运行过程中,无法通过维持偏离影响经济增长;(2)"贬值促增长"这一结论在发展中国家中显著成立,原因可能是其倾向于实施外部导向型政策来维持被低估的实际汇率进而推动增长。另外,正向关系对于中低收入国家以及实际汇率被低估国家始终成立。     

人民币真实汇率调整的非线性性比较研究——基于非线性类型与基准货币选择

采用1994年1月—2014年1月度数据,对人民币兑美元、英镑及日元实际汇率的非线性调整行为进行了比较研究。结果表明,人民币实际汇率目前已经达到均衡水平甚至处于高估状态。2014年1月,人民币兑美元实际汇率高估约10%,人民币兑英镑实际汇率高估约7%,人民币兑日元实际汇率高估约12%。三种基准货币下的人民币实际汇率均具有显著的非线性特征,但是不同基准货币下的实际汇率具有不同类型的非线性特征。具体地,人民币兑美元实际汇率的调整过程具有ESTAR特征,人民币兑英镑实际汇率的调整过程具有LSTAR特征,而人民币兑日元实际汇率的调整具有SETAR特征。最后,人民币兑美元实际汇率具有均值回复特征,满足长期PPP假设。     

人民币汇率严重低估了吗?

本文主要讨论了人民币均衡实际汇率以及汇率错位问题。在归纳测算均衡实际汇率的主流经济理论及方法之后,文章回顾了近期文献对人民币汇率偏离的实证结果,后运用3种检验手段对人民币汇率失调幅度进行测算与判断。研究表明,目前的均衡实际汇率测算方法各含缺陷,且人民币汇率在1996-2007年间未出现严重错位现象。根据目前国际收支失衡的局面,我们建议:大力发展服务业;扩大进口并优化进口格局;灵活运用汇率制度与价格政策相结合的机制,从而保障汇率更加平稳、趋于均衡。     

韩元的长期均衡性分析

本文采用购买力平价（PPP），国际费雪效应（IFE）和一般购买力平价模型（G—PPP）对深受亚洲经济危机打击的韩元的长期均衡性进行经验研究。在计量方法上，首先运用增广的迪基一富勒检验（ADF）对真实汇率进行稳定性检验；其次运用Engle—Granger两步法对购买力平价再次进行验证，并检验两国间利率差的变化是否对汇率变化产生影响；最后采用Johansen的多变量协整分析方法，对5组真实双边汇率间的长期均衡关系进行检验。检验结果表明：第一，通过对整个样本和亚洲经济危机以前的样本分析，证实了韩国和主要发达国家美国、加拿大、英国、日本、新加坡之间购买力平价关系不成立；第二，亚洲经济危机以后，除了韩国和美国外，韩国和其他主要国家间购买力平价关系得到成立；第三，两国间名义利率的变化对于两国间汇率变化存在一定程度的影响，从而证实了国际费雪效应的存在；最后，虽然整个样本期间5组真实汇率间均衡关系不成立．但是亚洲经济危机以前事实上存在均衡关系。     

人民币购买力平价成立吗?——基于人民币兑欧元的多样本协整分析

选取人民币兑非主权国家货币——欧元的名义汇率,中国CPI指数及欧元区调和HICP指数的数据,以欧元正式成为欧元区唯一合法货币的起点2002年7月到2018年12月为样本,依据影响中欧汇率的重要节点事件对样本进行分段与结合,对人民币兑欧元购买力平价(PPP)成立与否进行协整检验。实证结论有:人民币汇率形成制度改革及欧元平稳运行后的(2005年8月—2018年12月)人民币兑欧元购买力平价协整检验成立;非主权国家货币欧元同样适用经典的购买力平价理论;2008年金融危机是影响汇率市场的重要节点事件,但长期不影响人民币兑欧元购买力平价成立;对PPP冲击影响最大的首先是汇率本身,其次依次是欧元区HICP、中国CPI。因此,购买力平价在一定程度上能够解释人民币兑欧元汇率,对中欧经贸往来有一定的指导作用。     

人民币名义汇率制度非中性辨析

2005年7月21日的人民币汇率制度改革,为检验名义汇率制度是否中性,提供了一个案例机会。此次汇改,在“事实”上提高了人民币与美元双边名义汇率的弹性,降低了人民币与非美元货币的名义汇率弹性以及名义有效汇率的弹性。名义汇率波动程度的变动使得人民币美元双边实际汇率的标准差变为汇改前的大约两倍。但降低了人民币欧元、人民币日元的双边实际汇率和人民币实际有效汇率的波动幅度。结果表明,人民币名义汇率制度是非中性的。     

人民币均衡汇率再思考北大核心

本文回顾了均衡汇率决定理论,通过比较不同均衡汇率的估计方法,选择了行为均衡汇率(Behavioural Equilibrium Exchange Rate, BEER)方法对当前人民币实际均衡汇率和实际汇率进行了偏差分析。本文的模型反映利差扩大、人均GDP增速抬升、财政收支稳定、贸易状况不确定性下降以及境外资本净回流本国将使实际汇率升值。本文所选样本期为2015年3月至2021年12月,所选样本期内多数时间阶段实际汇率与实际均衡汇率均存在不同程度的偏离情况。本文研究表明,自2020年6月至2021年12月以来,人民币存在一定程度的汇率偏差。2021年第4季度人民币实际均衡有效汇率区间为6.48—6.55,反映了人民币汇率仍处于合理均衡波动区间。考虑到国内经济结构和国际局势的日益复杂性,长期来看,未来为了更好地避免外生不确定性冲击对中国汇率的影响,坚持汇率制度改革将是长期必经之路。     

人民币实际汇率影响国际收支的实证研究

通过用2009年1月—2011年12月的月度数据,建立实证模型,用单位根检验、协整检验等方法分析了人民币名义汇率对调整国际收支的影响。结果表明,人民币实际汇率的升值会导致出口减少。假设出口值减少导致净出口减少,那么净出口值的变动将促使人民币实际汇率反向变动。     

Getting PPP right: Identifying mean-reverting real exchange rates in panels

Recent advances in testing for the validity of Purchasing Power Parity (PPP) focus on the time series properties of real exchange rates in panel frameworks. One weakness of such tests, however, is that they fail to inform the researcher as to which cross-section units are stationary. As a consequence, a reservation for PPP analyses based on such tests is that a small number of real exchange rates in a given panel may drive the results. In this paper we examine the PPP hypothesis focusing on the stationarity of the real exchange rates in up to 25 OECD countries. We introduce a methodology that when applied to a set of established panel unit-root tests, allows the identification of the real exchange rates that are stationary. Our results reveal evidence of mean-reversion that is significantly stronger as compared to that obtained by the existing literature, strengthening the case for PPP.     

Testing the Purchasing Power Parity Hypothesis for the New Member and Candidate Countries of the European Union: Evidence from Lagrange Multiplier Unit Root Tests with Structural Breaks

This paper investigates the validity of purchasing power parity (PPP) for the eleven Central and East European transition countries and three market economy countries, Cyprus, Malta, and Turkey. Unlike previous studies on PPP, this study uses Lagrange multiplier (LM) unit root tests that incorporate structural breaks in the data series. The findings indicate that in cases of one and two structural breaks, for a U.S. dollar-based real exchange rate series, there is little evidence supporting the validity of PPP. For a deutsche mark-based real exchange rate series, for the cases of both one and two breaks, there is evidence of stationarity of real exchange rates for eight sample countries, which is consistent with PPP. The results also indicate that the estimated half-life of a shock to the real exchange rate ranges from 1.25 (15.05 months) to 2.72 (32.72 months) years across countries. The empirical findings may provide direction for policy makers to coordinate monetary policies for the process of European monetary integration.     

Why panel tests of purchasing power parity should allow for heterogeneous mean reversion

Recent studies of purchasing power parity (PPP) use panel tests that fail to take into account heterogeneity in the speed of mean reversion across real exchange rates. In contrast to several other severe restrictions of panel models and tests of PPP, the assumption of homogeneous mean reversion is still widely used and its consequences are virtually unexplored. This paper analyzes the properties of homogeneous and heterogeneous panel unit root testing methodologies. Using Monte Carlo simulation, we uncover important adverse properties of the panel approach that relies on homogeneous estimation and testing. More specifically, power functions are low and assume irregular shapes. Furthermore, homogeneous estimates of the mean reversion parameters exhibit potentially large biases. These properties can lead to misleading inferences on the validity of PPP. Our findings highlight the importance of allowing for heterogeneous estimation when testing for a unit root in panels of real exchange rates.     

Testing for long-run PPP in a system context: Evidence for the US,Germany and Japan

This paper extends the current literature on PPP by re-examining the validity of the PPP hypothesis for the three key currencies of the recent floating exchange rate period, in a multilateral framework. We argue that PPP testing is more adequate in a system context, which takes into account the dynamic interactions of exchange rates and prices of more than two economies, simultaneously. In the system analysis framework, some form of causality among the variables under consideration is also assessed empirically with the aid of weak exogeneity tests. The results illustrate the importance of the multilateral testing. Positive evidence for PPP is found: long-run PPP is supported for the US and Germany but also for the US and Japan, in contrast to evidence of earlier empirical studies. In addition, causality is found running from the US prices to the exchange rates and German and Japanese prices.     

Local persistence and the PPP hypothesis

This paper examines the statistical properties of the bilateral real exchange rates of the U.S. vs. France, Germany, and the U.K. during the Post-Bretton-Woods period, and draws implications on the Purchasing Power Parity (PPP) hypothesis. Contrary to traditional studies that consider only unit root and stationary processes to describe the real exchange rate behavior, this paper considers an in-between process, the locally persistent process. The empirical results demonstrate the following two findings: (1) Locally persistent processes describe the real exchange rate movements better than unit root and stationary processes, which implies that PPP reversion occurs and PPP holds in the long-run. (2) The confidence intervals for half-life deviations from PPP under local persistence tend to be narrower than those obtained by assuming the ADF and the local-to-unity models.     

Real exchange rates and nontradables: A relative price approach

In this paper, we study long-run comovements of real exchange rates and relative prices of nontradables and tradables. This approach is complementary to many existing approaches to investigating real exchange rate movements. In many theoretical models of exchange rate determination, the relative prices of nontradables and tradables are linked to the real exchange rates by identities. However, they do not necessarily move with real exchange rates in reality because of many factors. For example, many tradables contain nontradable components in the form of retailing services, so that Purchasing Power Parity (PPP) may not hold for these tradable goods even in the long run. Hence real exchange rates may not move in the direction predicted by theoretical models when the producers of these tradable goods experience changes in productivity. In this paper, we identify time periods, countries and relative price measures for which comovements between real exchange rates and relative prices of nontradables and tradables are observed.     

Purchasing power parity, unit roots, and dynamic structure

Recent studies of purchasing power parity (PPP) account for the possible presence of unit roots in nominal exchange rates and relative price indices by applying standard unit-root tests to real exchange rates, which are ratios of nominal exchange rates and relative price indices. These studies occasionally find evidence of PPP, but as a whole, the evidence is not definitive. Standard unit-root tests impose a restrictive dynamic structure between nominal exchange rates and relative price indices. I specify and estimate a generalized dynamic structure. I reject the dynamic restrictions implicit in standard unit-root tests of PPP, and find stronger evidence of PPP than do most other recent studies.     

A test of purchasing power parity for emerging economies

The concept of purchasing power parity (PPP) is examined here for its applicability to the soft currencies of a large group of emerging/developing economies. PPP is tested through the use of the technique of cointegration. Based on data covering the period of 1975–1997, cointegration tests of price indices and exchange rates are conducted for 27 countries (against the U. S.). The results provide relatively strong evidence (for 14 countries) in favor of the long-term applicability of PPP as a cointegration concept. Further tests on real exchange rates indicate that the symmetry and proportionality conditions implied by PPP are rejected in all but one case. The latter tests also show that departures from long-term exchange values can last for several years and that a priori restrictions imposed on the cointegrating vector can lead to a false rejection of the PPP concept.     

Deviations from purchasing power parity under different exchange rate regimes: Do they revert and,if so,how?

We propose an empirical model for deviations from long-run purchasing power parity (PPP) that simultaneously accounts for three key features: (i) adjustment toward PPP may occur via nominal exchange rates and relative prices at different speeds; (ii) different exchange rate regimes may generate regime shifts in the structural dynamics of PPP deviations; (iii) nonlinear reversion toward PPP in response to shocks. This empirical framework encompasses and synthesizes much previous empirical research. Using over a century of data for the G5 countries, we provide evidence that long-run PPP holds, the relative importance of nominal exchange rates and prices in restoring PPP varies over time and across different exchange rate regimes, and reversion to PPP occurs nonlinearly, at a speed that is fairly consistent with the nominal rigidities suggested by conventional open economy models.     

Testing PPP Hypotheses between Japan and the Six G7 Countries

The paper examines the purchasing power parity(PPP) theory of the foreign exchange rate of the yenagainst the currencies of the six G7 countries. We usethe error-corrected five-dimensional vectorautoregressive (VAR) model with structural changes inthe trend function. The data cover the period of thepost-Breton–Woods floating exchange rate system. Theresults reveal that the PPP relation alone determinesthe exchange rates for the USA, France, Germany, andItaly, while a linear combination of PPP and uncoveredinterest rate parity (UIP) relations determines that for Canada. Ina model without trend breaks, the PPP relations holdonly for Germany, which indicates that a correctspecification of the sampling distribution of data isimportant. The one-step prediction based on the errorcorrection model (ECM) outperforms the random walkmodel. The ECM is useful to predict the out-of-samplebehaviors of the exchange rates.